Twitter I can thank Steve for this one. Twitter helps you stay connected through the exchange of quick, frequent answers to one simple question: What are you doing. I am using it to update my facebook
With Brightkite you can tell people where you are (googlemap included - freaky) and what is happening. You can also meet new people in the same space.
AudioBoo records short audio clips. They can be pasted into a blog, sent to a friend, updated to facebook or twitter. Very cool
If you are on any of these, let me know so I an add you to my friends list.
My user on all of the above is ColoradoNegrito