ProE, Autocad 10, Solid Edge, Sketchup
ProE I used for a class when I was in school. Autocad (this was an old dos version) I used at work for a few years, but that was all tablet based (like a grid where every spot was a shortcut, used a mouse like device with a cross hairs on it). Not very useful as the interface and functions were custom. Then we switched to Solid Edge. Very good for 3d, but sucked if you just wanted to do a 2d drawing without doing the 3d drawing 1st. Don't remember the version. I don't draw stuff for a living anymore. Now I solely use Sketchup for personal stuff, because it is very intuitive and have just enough features so there is no learning curve if say you leave it for a few months. And you can improve it yourself by writing plugins or downloading them. I was turned on to it when I got involved with the Phlatprinter. I wrote my first tutorial in March 2009, but it's posted at the phlatforum. If anyone is interested, it located here: http://phlatforum.com/viewtopic.php?f=94&t=653
It's about how to make a sliceform light buld, in Sketchup. I posted a pic of it towards the end of the cad/cam vote thread.