Would it be technically possible to build a forum plugin for various forum software that would permit the transferring/receiving of bitcoins? 

I'm thinking of a glorified thank you mod.  Currently most forum software has a plugin that allows one forum user to 'thank' another user.  Sometimes they can earn points from these 'thank-yous'.  I'm wondering if a plugin could be built that allows the thanker to donate a bitcoin or two to the thankee in as simple a manner as possible.

Bitcoind is the headless version of bitcoin that can be run on a server.

http://www.bitcoin.org/wiki/doku.php?id=headless_client&s[]=bitcoind