Need a Blu-Ray Player, AnyDVD-HD, and TwonkyVision:
http://www.twonkyvision.de/ or on alternative sites (look for PacketVideo)
You also need to have a wired networked connection between your computer and the PS3.
Rip the BD movie to your hard drive on your computer using the "RIP VideoDVD to Harddisk" option on AnyDVD-HD.
Create a Videos folder on your PC and move the ripped movie folder to it.
Start Twonky and point the videos folders out to twonky config page.
The PS3 should be able to see the Twonky server under the videos tab (and music and pictures if you have set them up in Twonky and on your PC). Keep going down the folders until you get to the stream folder for the movie. One of the .mts files is the movie (you can figure out by seeing which one is the largest file on the PC!). click on that file and the movie should start running.
reply back if you get it to work!