Help! D:

I'm currently in my work, I have a pretty weak laptop and a few MB of internet I can use, and I'm really bored. Can anyone suggest me a game which is;

1) weights very little, around 50MB at most?

2) With really really low hardware requiremnts.

3) Something fun enought to pass 10 hours.

4) On Steam.

Thanks for all suggestions!

EDIT: In the end I chose Hack, Slash, Loot. Weights only 8MB and is rouge-like which is always good for burning time. Thanks for all the ther suggetions.