I do realize that I keep going on and on about this high school alumni site I joined, but this post isn't about that site specifically. This post is about the fact that you can create your very own social network.
Go to www.ning.com and check it out. Family reunion? Friends from previous jobs? Cousins you want to keep up with? Start your very own MySpace-type network. Everyone can upload pictures and groups and discussions can be formed on specific areas of interest.
I haven't created my own network, so I'm not sure how simple it is to do that. However, based on the ease of use as a member of a Ning network I'm pretty sure it's a snap to set up your own space.