Most Ambitious thing You've Done?

I see a lot of more passive actors in the forums, and that's fine, but there are also a lot of Caliborn/Dirk lovers, which means there are people here who love Ambition. However, I feel like i don't see shows of such Ambition here that often.

So, to fix that, just answer this right here: What is the most difficult, ambitious thing you have accomplished? Extra points if it's not a thing forced upon you (like school/college/work) since that means you did an ambitious thing because it would be cool to do, and not just out of necessity.