Download the zip file and open tinyworld.html
You'll need a web browser capable of html5. Firefox 11 should work. Chrome and Opera seems to possibly be ok.
If you don't want to download music, just download the source code version.

Source code is included in all versions. binary version filesize ~8megs.

md5 sums
46807cad4e4e95e3937838c1c0b76d4f *maniksinha_ludum23.zip
15a913645a5c24ba329f453f9417c6ef *maniksinha_ludum23_src.zip

Instructions:
Move around with the arrow keys(hold shift to move quickly).
Surround the circles on all 8 of its sides to make it disappear.
xxx
x0x
xxx
Extra Keys:
[X] toggle snake mode
[Z] Use Z to place blocks when not in snake mode.
[C] [V] [B] c,v,b all related to color press to find out.
[-][+] keys to spawn and kill enemies
[ and ] keys to increase/decrease the maximum number of boxes you can place.

There is no end condition just play as long as you want. Try out different box length sizes and enemy quantities.

TroubleShooting:
If you have trouble moving around, try clicking on the game to give it focus. It's not focused by default.