Angelfire
This, obviously, is the provider of my website, which you're looking at right now. (My site was originally on GeoCities, but in 2000 somehow I lost access to it, so I moved to Angelfire, and have of course added and improved a great deal in the year since then. "Absolutely Pointless" is still fairly simple, by design, but I like it. I'm sure you could make a much more sophisticated site on Angelfire, with the proper skills and effort.)
The A.V. Club
This has been around for a lot longer than I've made much use of it. But I think it must be in early 2015 (or 2014) that I started including links to it on some of my TV reviews, and late 2015 that I started regularly reading episode reviews the site does of some of the shows I watch. (The site reviews a lot more than just TV, but that's pretty much all I use it for.) Anyway, I don't always agree with what the reviewers have to say; sometimes I feel like we couldn't possibly have been watching the same show. But a lot of the time I find reviews insightful well beyond my own ability to perceive certain aspects of the shows I watch, which gives me a deeper appreciation of those shows. And sometimes I just find the reviews amusing, or just enjoy seeing that someone else had some of the same thoughts I did. Anyway... it's a good site.
Babel Fish
This was originally a translation device on AltaVista, starting in 1997. Later, in 2008, it moved to Yahoo! After that, in 2012, I guess it became the Bing Translator. Though there's another translation device called Babel Fish, which has been at that URL since 1995, though I don't think I became aware of it until November 2013. (Which is also when I first discovered Yahoo's translator had moved to Bing, which is odd because I've definitely used it between 2012 and now. Maybe I just didn't notice that the link was being redirected, until it stopped being redirected.) Edit: In 2019, I received an email from someone suggesting I add a link here to an article about the rise & fall of Babel Fish, which is a nifty little lesson in a bit of internet history that you might want to check out.
ComingSoon.net
Has plenty of info on TV, movies, and DVDs, though I mainly just use it as reference when working on my site's calendar.
Everything2
Kind of like Wikipedia (see below), but not nearly as cool. (It doesn't even have pictures!) Still, it's not bad, either. Although it's often very slow-loading. But not always.
Facebook
Yes, you know the site. For social networking, playing games, etc.
the futon critic
Has plenty of info on TV stuff, though I mainly use it as reference when working on my site's calendar.
Google
Best search engine ever. So far. I dunno, plenty of other search engines have been the best search engine ever, and they're all still good. But this one has held onto the top spot longer, it seems. And it's simpler, which is nice. And it has cool logos (aka Doodles) for special occasions. It also works better as a verb than any of the other engines do. Plus, it offers Gmail. I know, all the major search engines offer email. But Gmail is zeitgeistier, okay? Just like the search engine itself....
The Guild
Best. Webseries. Ever.
The Hollywood Stock Exchange
A really fun game trading fake stocks, bonds, and such, in movies and movie stars.
Hulu
Great for watching shows online, like if you miss an episode or if you don't have the channel a show's on, on your TV. Or you can watch movies, too. And there's some original content.
Edit: Hulu used to have some content for free, and some available only by paid subscription. I never could afford to subscribe (not that it's expensive), but I always enjoyed some of the free content. However, in early fall of 2016, the site ceased offering free content, so... I had no choice but to stop using it. I expect someday I'll subscribe, if I can ever afford it (and if I have reliably fast internet), but until then, it's no longer one of my favorite websites.
Edit 2: In late November of 2018, I took advantage of a deal to subscribe for 99 cents a month for a year, so now it's at least temporarily a favorite website again. And after that year ended I kept subscribing at regular price.
The Internet Movie Database
One of the most useful reference sites on the Internet, for info on movies, TV, cast and crew, etc. I've submitted a little data, occasionally.
Neopets
Take care of the cute critters of your choice, lots to choose from. Plus play any of countless other games to earn neopoints, to pay for the stuff you need to take care of your pets. (Sadly, my account was frozen in early 2017, and I haven't been able to use the site since then. I could probably join up again and start from scratch, but I really don't want to do that.)
Nihongo: Japanese Language
Very useful if you're interested in translating English words into Japanese, and vice versa. Though unfortunately the site sometimes fails to work for some reason, when it is working it's pretty good.
Retro Junk
Great site with pages for lots of TV shows, movies, and commercials from the 70s, 80s, and 90s, often with opening or closing themes for shows, or trailers for movies.
Snopes.com
Very useful for debunking rumors and fake news.
Things From Another World
A great site for ordering, like, comic books or anything comics-related. If for some reason you can't get it at your LCS (or if you live nowhere near a comic shop).
Things my girlfriend and I have argued about
One of the funniest things on the Internet, written by British columnist Mil Millington. If you don't read this, you... won't know what you're missing, and I think that's just really, really sad. I don't think it's updated anymore, so I don't look at it anymore, but it's still one of the best things ever.
TV Tango
Has primetime TV listings going back to 1950. I've found it useful for reminding myself of things I have watched as far back as the 80s, but may have forgotten. Or for finding out exactly when certain things aired. Unfortunately, the farther back you go, the less channels are covered... at least in the regular listings. Though you can always search for something specific and may find a page for it even if it's not in the listings. Then again, there are also gaps in the listings sometimes. And I'm not sure exactly how they determine their listings. I know they don't seem to accept any other website as a source, even if the website is correct, and sometimes I think TV Tango is wrong about what it says. Like, I would guess they use print listings such as TV Guide, like physical copies from the time in question... which itself could be wrong, if shows got preempted or whatever. So... I dunno. In spite of the site's best efforts to ensure accuracy, it may sometimes be inaccurate. But on the whole, I think it's very useful, and sometimes may be more accurate than most other sites you look at. And while the information it provides tends to be minimal, it can sometimes provide info that you simply won't find anywhere else. (For example, it's usually the most useful site I know of for determining whether something was a TV movie or a miniseries.)
TV Tropes
A wiki which prides itself on being more fun-loving than Wikipedia. It was originally for TV shows, but now includes movies, books, comics, etc. The number of tropes this site has catalogued is truly staggering. Definitely a fun and useful tool for getting to know various entertainments better, and seeing how they compare to every other entertainment ever. Or something like that. It can also provide some knowledge about specific people (writers, actors, etc.) or about more serious subjects. (It has perhaps the best explanation of Asperger's Syndrome I've ever seen.)
Urban Dictionary
I don't use this often, but still I think it's an awesome thing to have access to, any random time you might want to know what a slang word or phrase means...
Wayback Machine
I don't use this often, but I still think it's an awesome thing to have access to, any random time you might want to check out a site that doesn't exist anymore. Or if you accidentally deleted something on your own site and want to get it back.
Wikia
A great site to get your own wiki, or just to explore other wikis on countless subjects. You might check out mine, The Landian Chronicles Wiki. Oh, and I also started a Geek & Sundry Wiki.
Edit: The site eventually changed to "Fandom", but I still think of it as Wikia.
Wikipedia
Best encyclopedia on the Internet, and ever-expanding. Massively useful and cool. I occasionally contribute a bit, start a stub page if there isn't anything on a person or subject I think should be there, or make minor edits to existing pages, mostly adding external links. Check out my user page. HOWEVER, in January 2015, this happened, which is just outrageous, and makes Wikipedia pretty damn uncool. I can't just stop using the site, it's too useful. But now I feel guilty about using it.
Writing About Writing
This is Chris Brecheen's blog, which as the name suggests is mostly about writing. I started following it- and Brecheen's facebook page(s)- I think in 2014, because I had at least one friend who was already following it. And I figured it couldn't hurt to pick up some pointers, since I fancy myself a writer. Before long it also turned out to be a good source of articles about social justice (which I got quite interested in that year, because of various major events in the real world, involving racism and sexism, etc.), and also a good source of memes (some about writing, some about social justice, and some just amusing). And now... in late 2015, I finally realized I had to include the blog on my list of favorite sites. Because that's what it's become.
YouTube
A site that streams all kinds of video... music videos, vlogs, clips from TV shows, home videos, pretty much anything its users can think to upload. Unless it violates copyright laws. And of course it has some good channels, some of which provide original content. And I find the site useful for deciding whether to buy an mp3 from Amazon or wherever, because I can hear the whole song instead of just a 30 second clip.