Here's a little fun project of mine, a falling blocks game for mobile phones. Disappointed by low quality of all available Tetrii, and really wanting to play one, I wrote one myself. Primarily designed for small screen phones (although it requires MIDP 2.0, caution), it works on large-display phones just as well. At least on some of them that I tried. It's pretty advanced too, has shadow display, autorepeat, soft, firm and hard drops, SRS-compliant rotation, albeit without wall/floor kicks.. Anyway, if your phone has Java MIDP 2.0, check it out and send me feedback -- Link.