Do You Twitter?
maximumwage: I'm not on Twitter, but I enjoy following the feeds of top entrepreneurs and investors.  Here are a few good lists and rankings:
http://www.bigwinner.org/twitter-leaders/
http://buzzmarketingfortech.blogspot.com/2008/12/c-level-twe...
http://twittercounter.com/pages/100
http://twitterholic.com/