Sightspeed
It dawned on me that the relatives would like to see Christopher live instead of watching movies all the time. After seeing what the h264 codec could do for movies, I really wanted to get a video chat program that would work for windows and support h264. (On Mac I have iChat, but Windows folks are out of luck on that.)
Mom bought me an iSight camera for Christmas, which is really nice. It works okay on Windows, assuming your software can fix the insane overexposure that the camera has out-of-the-box. Windows also doesn’t recognize the built-in directional microphone. But the autofocus and overall picture are nice.
Next I looked into software. Streaming video supports h264 and multiple viewers, but has nasty delays. Supposedly AOL Instant Messenger supports iChat, but I just couldn’t get it to work. After much web searching, I finally found SightSpeed. The free service provides one-to-one chatting, and 30 second video mail. It even has a web-based viewer that family can use even if they don’t have SightSpeed installed (it downloads an ActiveX control). Perfect! (Well, not really since it doesn’t have h264 support.)
I expect that soon my family will all have webcams. 
If you want to connect to me, install SightSpeed and search for “coppit” as a contact. Be sure to enable the video mail so I can send you video clips when you’re not online.
By the way, I did try Skype, but its video interface was clunky.