Caffeine, lack of sleep, stimulating music, and exercise. I'm not physically active normally, so when I get that rush of energy I start cleaning everything that isn't running for the hills (usually in time to that stimulating music) and it feeds off itself. The hypomania feels good, which is why I let it happen...but then when I become manic, I get the angry, hostile kind of manic and it's not pretty. I'm on a lot of medication so that doesn't happen much anymore.