Rate of decay of enthusiasm levels

This is a dedication to all YSSPers and particularly to Stefan who sat through an incredibly geeky conversation with me about decay rates of enthusiasm post-YSSP. I'm sure each of you could add to the graph to make it more accurate. Disclaimer: The numbers are completely false!
I had a conversation last night with Warren about a portal for communication between YSSP 2010 participants post August. He was asking me as a CS geek to suggest possible means to facilitate long-term communication and sharing of news, reunions and resources. Now Facebook does not allow for resource sharing but does provide support to share photos and create events and has a discussion forum. Google groups can cater for both the forums and resources but not the photos. Any suggestions? This needs to be an already developed tool.