Heh....it would be virtually impossible as the keyboard is a slider, not to mention that the phone wouldn't dial without opening the phone app, which would appear on top of the DIVX player (read: porn) letting me know it was making a call.
It does kick ass for regular movies, though. I can compress a full-length DVD into about 300 MB and it looks great on any screen 4" or smaller. On my recent road trip to California we had two pocket pc's and my phone (which has a big screen for a phone) and had eight 1 GB SD cards. So we had more than 20 full length movies to choose from and enough players for everyone but the driver. Pretty cool. Also, if you already have a collection of ripped DVDs (which I do) you can change the resolution and shrink existing Divx movies really quickly. It only takes about 15 or 20 minutes to take a 1.5 GB DIVX and make a 300 MB version of it.