Usability 
JoJoC.mobi is the place for OTA BlackBerry game, theme and game downloads. It has 30+ themes for all models, about 50 backgrounds, 30 applications and nine games. All but a handful of the downloads are free. There are a lot of gems here including many commercial quality games and applications. The only real issue I have with this site is that it doesn't consistently indicate which device each download is compatible with. So you will waste a a little time downloading things that don't work but I think it's worth it given the selection and quality of JoJoC's downloads . Tip, on my 7100i, all the games in the "ScrollWheel" section worked except Texas Hold'em and Sudoku.