Louis C.K, writing on his website:

hi. So it's been about 12 days since the thing started and yesterday we hit the crazy number. One million dollars. That's a lot of money. Really too much money. I've never had a million dollars all of a sudden. and since we're all sharing this experience and since it's really your money, I wanted to let you know what I'm doing with it. People are paying attention to what's going on with this thing. So I guess I want to set an example of what you can do if you all of a sudden have a million dollars that people just gave to you directly because you told jokes. So I'm breaking the million into four pieces. The rest of his post outlines exactly what he plans to do with the money. Spoiler alert: he's a generous man. Andy Baio made a good observation on Twitter:

I don't trust keeping more than $200 in my Paypal account, and @louisck's has over $1M: buy.louisck.net/news
— Andy Baio (@waxpancake) December 22, 2011

Note that he left his Paypal account email in the screenshot. I wonder how many people are trying to hack the account right now.
— Andy Baio (@waxpancake) December 22, 2011

I do hope Louis C.K. moves that pile out of Paypal to a safer location, and soon.