Okay, I've got about the most rudimentary collision-detection system possible in place. But it is in place. Next let's do shooting & enemy AI? Moving left & right 'll slightly change the ship's momentum (very slightly) and I think it might be cool to have the ship's momentum slightly (again, very slightly) affect the angle @ which it shoots. Flocking AI for some enemies. Flocking is really beautiful in practice and I think enemies in a shooter is the perfect application for it. -could do something really cool w/the adaption of this. Add some sort of flocking rules to the player's bullets. Some sort of laser, spread, fire? Going to have to keep track of lots of bullets onscreen. So... Hey, what about that special-purpose programming language that guy uses to make those shooters? I don't think I necessarily want to use it, but it may be helpful. I don't know if an array is the best way to store bullets/enemies. The # of elements is constantly going to be changing. A linked list seems like a good choice - I've never really worked w/em, true, but the principle is pretty straightfoward. Can probably do a one-way linked list, but two-way is possible if I ever need to traverse it in reverse (or don't know the prior element beforehand) I'm going to need a really good collision-detection algorithm. I'll probably want to break the screen into sectors... That's tough: I don't really know how to go about it. But now's the perfect time to learn.