4. Super Meat Boy
This new crop of nostalgia-based platformers like Super Meat Boy and VVVVVV are fantastic fun. They are also harder than taking the GRE on no sleep and zero Adderall. Super Meat Boy makes world eight of the original Super Mario Bros seem like hugging a sleeping puppy. That's how hard it is.
Now, I don't want to generalize, but dealing with grueling difficulty is not high on a stoners' “to do list.” Games that feature exploration, or just a bunch of pretty colors, are ideal for smoking. Games that force you to re-do the same level over and over (and over) could induce some serious smokers regret.