While on a shoot with an HD camera you will almost definetly here the question
"What is the 35mm equivalent of this lens?" Well you can do some fancy math... or use a handy cheat sheet from Panavision. Of course it's only accurate for Panavision lens but it give you a pretty good idea of what your seeing in a 35mm equivalent across the board.
You can down load the full PDF and a simular one here from Panavision's website. This was another gem from Les. He has a photo copy of a photo copy of this document and I did some digging with the help of Johnny B at work and found this on the web.