What have been some of your "aha" moments?

And how often do you get them while at work?

One that i can remember was after solving a problem with spring initializing beans after working two days straight on it, I realized my attempts at "problem solving" up to that point had been downright pathetic I had been giving up way too early and way too easily.

I now seem to get one of these moments between every 2-3 months of mashing buttons on my keyboard