Alibre CAD
 

I couldn't see Alibre mentioned here, so thought I'd throw this out for anyone interested. There is a free version - "Xpress" which I've been using it for a few months and have found it to be generally pretty straightforward and capable. You are limited on part count for assemblies, so not much help for complex creations, but for creating 3D parts and saving views/sections to DXF it is very good. The full version normally goes for between $600 and $900 (US), but there is currently an offer running until September 26th or thereabouts where you can get the full version for $99. I'm in the UK and hate paying the Brit-tax rate of £99, so tried purchasing directly through the site rather than a reseller and it worked! Upgrades/maintenance costs more ($299), so I'm still deciding whether I really need that, as the current version does everything I want at the moment and has no limits on assembly size.
In case anyone is interested, the link for the $99 offer is: http://mkt.alibre.com/l/1004/2009-08-04/EI16A

Also Alibre team up with Mecsoft who produce Rhinocam, and came out with Alibrecam .
http://www.alibre.com/products/ac.asp
Normand