A new Humble Indie Bundle was just released! Go get it! It contains some seriously cool titles like:
Super Meat Boy: Seriously, this game is frustrating. If you are easily angered by repeatedly dying horribly, or are offended by sentient blocks of meat, do not play this. If the above stipulations don't apply to you, GET IT. If you ever played I Want To Be The Guy, it is a lot like that.
Bit Trip Runner: I love the Bit Trip games. They are just so simple but amazing. The music and sound are top notch, the gameplay is addicting. Altogether, this is probably my favorite part of the bundle, even though I already own it.
Jamestown: I think this one is considered a bullet hell but I could be wrong. The setting is great and it has a lot of that old fashioned arcadey goodness thrown in.
I haven't played most of the other games. Cave Story + is probably great, as it is an updated version of the old fashioned Cave Story game.
Make sure you pay at least 5 dollars. (Hopefully more!) Because at 5 you currently beat the average. I would say at least spend ten bucks or you are a jerk.