Facebook, Twitter and LinkedIn

I am using Twitter more lately because of a program called Tweet Deck.  I am also using Facebook more and adding friends from Task Force Diablo (2-104th GSAB) and high school.  You can find me on either Facebook or Twitter by searching my name.  I am also on Linked In but use that less.  Twitter and Facebook are made for immediate updates.  LinkedIn not so much.

I know there are hundreds of other social media options out there.  Are there specific ones an old soldier/chemistry geek/bicyclist should be looking at?

Let me know.