I used to room with a guy whose dad was a copyright lawyer. I found someone on eBay selling items printed with artwork I had drawn and posted online - "fanart" of a copyrighted character. I asked my friend to ask his dad if there was anything that could be done and the short answer was no. Years...
I'm curious to know the answer to this too. I did peruse the other topics in this section and the general consensus to this question seems to be "none" as belonging to and posting on a private forum is a privilege not a right, but if that's not the case I'd like to know.