I have a PS3 and I use TVersity. It works great, but be aware that if it's not a file format that is natively supported by the PS3 your laptop will have to transcode it on the fly, which can take a fair bit of processing power. Also, you may not get great results if you're trying to send any hi-def video over wireless.
TVersity also works on the Wii, but it's pretty useless for video. Everything gets transcoded to Flash (because it has to play inside the Wii browser), so the best I've been able to get is choppy, pixelated, lo-res playback. It's not too bad for music, though.