I just finished writing two papers together with my co-authors Shakib Manouchehri and Andreas Kuhlenkamp from the Research Centre for the Design of Information Systems, University of Kassel (Germany) on the application of social software in the corporate context (both will be published in German during the next couple of months and I will upload them as soon as the publishers allow). One interesting aspect in terms of knowledge sharing and adoption of innovative practices we discovered was, that people tend to use social software applications in their private life first and from there it is slowly migrating into the corporate context as a grass roots initiative.
This started to make me look at my personal behavior when it comes to using social software tools and I noticed, that at the beginning I tried everything, opened accounts and pages whenever a new tool popped up. But after a while I filtered out what was important for me and now I focus on openBC, sometimes Friendster and LinkedIn (when friends alert me to look at it again) and Flickr to share my fotos.
There is a great website called BigHugeLabs.com which lets you do all kinds of neat stuff with your pictures, like mosaiks (download as jpg and send it around or make postcards out of it), or the attached profile (love it!):