I was on the phone today with a Team Mate, Jacob Cynamon about the difficulties in presenting for a living. It's amazing how crytical developer audiences can be. :)
It reminded me taht I recently read a useful book for people who present in their jobs.
"Great Demo" - by Peter Cohan of "The Second Derivative".
To some extent it's focused on technical sales folks, but it's really a super resource for anyone who speaks on technology issues.
Check it out !