Display Share will set you back $50 and is currently only available for PC, though a Mac version is apparently in the works. Gaming is not recommended due to a substantial amount of lag, though this causes no problems for video files. It sounds like a decent application, even if the price tag is a little high. For anime fans looking for a solution to the PS3's lack of .mkv support, however, it could be a God-send.
[Via Ars Technica]