I like coding small games. Its fun playing a game that you created. Three things that i found are a challenge to make a good game are:
a. making the physics look decent
b. creating a reasonable AI and
c. keeping the gamer interested in the game, though the game might be simple.
I use Macromedia flash. I will try to upload all the games that i have made. To ask for the source code, dont hesitate to mail me. Please note that i am not a serious programmer. I do it for fun. So dont be surprised if u come across some bugs. Do let me know if there are any. Happy gaming.