Yup, there is a way. Before I start I have to say that you have to be the cheatiest cheater in the entire history of cheatland to do this. Once you have the Ice Key, it will be on you're Banjo-Kazooie cartridge forever, even if you wipe every single game on you're Game Pak! This may seem cool now but when you're version of Banjo-Kazooie is completely knackered, it may not have seemed such a good idea. My advise is to leave Banjo-Kazooie as it is and wait until Banjo-Tooie is released. But for you cheaters out there, here it is:
FIRST YOU MUST GET A GAMESHARK. A GAMESHARK IS A VIDEO GAME HACKING DEVISE PROGRAMMED TO FIND SECRETS IN GAMES THAT THE PROGRAMMERS DIDN'T THINK POSSIBLE. ON BANJO-KAZOOIE, THE CODE THAT YOU HAVE TO TYPE IN IS D0281251 0020 8137C4BC 43E0. THIS ACTIVATES THE MOONJUMP CODE. WHEN YOU PRESS 'L' ON YOUR CONTROLLER THEN YOU WILL JUMP UP AS FAR UP AS YOU WANT UNTIL YOU LET GO OF THE 'L' BUTTON. AS SOON AS YOU HAVE TYPED THIS CODE IN GO TO WOZZA'S CAVE AND STAND IN FRONT OF THE LEDGE WHERE THE ORANGE JINGO IS. MOONJUMP OVER THE ICE WALL AND THE GAME WILL REGISTER THAT YOU'VE GOT THE ICE KEY. FROM THEN ONWARDS WHEN YOU GO TO THE 'VIEW TOTALS' SCREEN YOU WILL HAVE A NEW SECTION ENTITLED 'STOP 'N' SWOP'. THE IDEA IS THAT WHEN YOU HAVE BANJO-TOOIE YOU WILL HAVE TO STOP YOUR GAME WITH THE 'STOP 'N' SWOP' SCREEN ON, TAKE OUT THE BANJO-KAZOOIE CARTRIDGE AND INSERT YOUR BANJO-TOOIE CARTRIDGE. THE ICE KEY WILL THEN BE SAVED ON BANJO-TOOIE!!!