As a developer, these are the moments I live for:
Yesterday morning my Muse payed me an unusual visit while I was taking a shower. One moment I was shampooing my hair, then suddenly I was hit by an incredibly detailed vision of how a key part of my project could be rewritten for better performance. I could literally see, line-by-line, the hundreds of lines of modified code and the new data structures required to make it work. I rushed to work (rinsed my hair first though and put on a towel), jumped into my chair and by the end of the day it was complete: Our mainframe parser, which had previously peaked at 10 pages/sec after many months of development and tuning, was running at over 60 pages/sec!
I don't know what my muse was taking that day, but I want some of it too :)