Jon "DVD Jon" Johansen writes, in reference to VLC's support for iTunes's M4P DRM format:
In case you didn't know, I'm a VideoLAN developer. I reverse engineered FairPlay and wrote VLC's FairPlay support. It's been available in VideoLAN CVS since January, but the first release to include FairPlay support is VLC 0.7.1 (released March 2.).
Just wanted to let you know that once you have generated the user key file(s), you can copy them to as many computers you want and play your M4P files there using VLC.