This may be an akward question, but I was curious and don't see the harm in asking. Who or what supports this site? I get the feeling it is a University, but that is a guess.
If it ever needs donations I'd be in that number, I like it here.
This is not an answer but I am also curious. I think the key to its success is its non-commercial nature. It's just people looking for information or help and others who are happy to provide it. One look at the number of forum members (more than 41000) tells you a lot. I suppose many of them are not active but this forum is surely tapping into a very vigorous dynamic. It's like Facebook for people who think.
The server gets paid for by running Google Adsense on the E-Books pages (not the worksheets or videos). These ads are not displayed however, if you have visited the forums. This applies to both guests and registered members (as long as the visitor has cookies enabled).
If you never wish to see ads on AAC, as well as most of the web, check out Adblock Plus
Nothing is free, and a little advertising is expected. AAC is particularly enjoyable compared to some other sites that have so much advertising it takes forever for a page to load.
Will the cost not go up ?
When I entered the forum last May there where about 20420 members.
When you look at the counter now it is already more than double.