with about 10000 daily active users, guessng about half of them donating to gaia every month, on an average of 3 donation letters per user (not counting those users who spend hundreds of dollars) id say that gaia gets more than enough to run the site. thats like 35000 dollars.
guessing 5000 users donate about 7 dollars making 35000. thats a lot. x_x <3
then think about those users that spend like 500 dollars to get like 100+ donation letters. woah.