Well for a little project I've decided to build a coilgun. The design is easy and I've already got a small working prototype but it's simply not powerful enough. Right now I'm using nine 16v 2200µF capacitors in parallel and I am able to launch a small metal projectile (the projectile is about the equivalent to a .30 caliber bullet) down a large straw. But I am itching to use some of the 200v capacitors I got out of some old power supplies, the problem is I simply do not have anything that puts out 200v DC to power these capacitors. I am only using a computer PSU to power the capacitors (only puts out 12v) and I need to get that to 200v or at least 150v DC. Is it possible to combine a bunch of PSU's to get more voltage output or is there another way to build something similar? I have a large amount of PSU's and many other electronic goodies at my disposal I just need help finding something that will work. I would strongly prefer not to buy anything since I have so much junk sitting around here right now that needs some using.