> PS3 support will require an additional device regardless of the remote you get.
Which additional device would I need?

> Could you clarify what you mean by "mouse control"? If you mean actual mouse cursor control for a PC... it's unavailable except in dedicated-purpose PC controls.
I have a Silverstone HTPC case for my mythtv machine with a IR receiver on the front. The remote has a pad which can be pressed in every part of the circle for input. However, I suppose up, down, left and right would be sufficient. Seeing how its just a IR remote it should work fine, no? Here is the remote:
[Link: wiki.linuxmce.org]