As thenewgreen said, this is all part of our ongoing discussion. Personally speaking, I would like to have no recognition, and nothing else associated with it. That's because I can see some non-donating users contributing to the site more than donating users, and although the non-donating also can get recognition via badges, shares, etc., it is earned on an even playing field that everyone has access to. Money is a good proxy for money. I'd like best if people donated (or didn't) based on their own reasons and means. I realize that this might be too idealistic, but that is my personal preference.
What about an indicator that is only visible to you? I like the idea brought up already, about showing how much you've cost the site, and how much you've paid for it. It might be interesting to show some stats like BitTorrent seeding next to your name, probably your "balance" and your ratio. But maybe only turn those on after the first time you donate, and definitely only visible to you. Oh, and the alt text could say "Thank you for donating!", and possibly provide extra stats.