You have got to check out Voice Thread! Talk about a great way to create an oral history, a travel log, a family-oriented audioblog -- you name it. I'm just sitting here thinking about how teachers and librarians could use this with teens as a way to connect them with their family history, and talk about a nifty tool for some intergenerational programming. I also think this could be a good tool for those who would like to try an alternative to traditional screen casting.
Be sure to check out What is Voice Thread, anyway?, and the basic tutorial, here.
Here are some threads you might find interesting:
My Facebook Experimentation
Vassar Island in Second Life
Online Teaching and Learning
OK, I MUST stop now (why do I think I'm going to blow a good chunk of the day playing with this?). Have fun!