JogaBonito - I don't think he's looking for that. I think he's looking for an input into the laptop so that he can use the laptop screen as a monitor.
Try looking for a Video Capture USB or PCMCIA (cardbus) adapter, and make sure it has either HDMI or if you can't find any with HDMI, find one with component.
unfortunately i havent found any that have HDMI or component, and the only USB 2.0 or PCMCIA cards that have HD-capability are the ones with Coaxial jacks. (remember, yellow/white/red is NOT what you're looking for)
If you could somehow get your PS3 to output through coaxial (the screwy jack) either thru a receiver or converter or something, then this you could get an HDTV tuner for your laptop or a USB 2.0 device that could do it, and then just fullscreen the monitor that views whats plugged in.
Another problem is that even if you did find a way to theoretically do it, there might be a delay which will not help you in gaming. Although sometimes you can go to the Windows REgistry and apply a patch that prevents this delay (a lot of Hauppauge cards are like this because they have hardware encoders which the video runs thru, delaying the picture by about a second).
either way good luck defcon, and congrats on your PS3. I hope you use it to its fullest extent.