Thanks for the thought Corniger, but to be honest we were given a pretty decent grant to kick start this project several years ago. That money has long since gone, but we prepaid all our hosting expenses so right now Alchemy doesn't cost anything but the time we put into it.
We aren't in this for the money so don't have a donation button

We are in it for the love so have a
Contribute page
But seriously, rather than trying to extract $2 out of every user, we would far rather they find some way to contribute and build the community. That could be the stuff listed on the above page or by blogging about Alchemy (right now we are
#6 on google and we would like to improve that!), telling your friends to try it out, teaching classes using Alchemy and other open source software, referencing Alchemy when you create and post artwork on other forums etc etc... This is all stuff that everyone can do to grow Alchemy in the long term.
As for money, well I would much rather find some big generous company that loves what we do and can sponsor some amazing programmers to implement our crazy ideas! The Google
summer of code would be nice actually.