So I'm leaving to move to uni on the 19th, and I will be leaving my main desktop behind. For whatever reason if I am stuck in halls on a lonely night and need something to play, can you guys reccommend games that have high replay value, but will run on a laptop with 1.6Ghz duo core, 512mb ram and a 128mb graphics card! 
 
I'm not talking about story based games which you could play over again (cause i don't think you could 

 ) but instead games like plants Vs Zombies, defense grid, that sort of thing.
Thanks