I look for math problems that have been unsolved for centuries ( even though I don't even like math and barely passed my math exams in school), or suddenly decide to become the greatest gamer or artist the world has ever seen. 

The feeling fades in a few hours. Sometimes the motivation lasts for a day or more. But the inspired I-can-do-things-no-one-knows feeling fades away and later I rarely even remember that I was once driven to do math or gaming or art. The depression sets in. 

I've been diagnosed with BPD, PTSD, Major depressive disorder, Obsessive Compulsive Personality Disorder and Schizoid Personality Disorder.