Create your own "About Me" page or make a resume on the fly.
This service may bring out the headhunter in everyone. Match up your colleagues on LinkedIn and Facebook with available positions (currently tech related) and you could be rewarded with serious cash. Just make sure to share.
Use this tool to get a visual representation of who is connecting with you on Twitter and around which hashtags the interactions occur.
A new networking utility called Hachi is taking some of the best functionality offered by LinkedIn and is merging that with your social graphs from other services like Facebook, and soon Google contacts, Twitter and even your Outlook address book.