Engineering students? Check this out.
Thought this might be helpful.
Autodesk, the company that makes AutoCad, gives out free 3-year licensed downloads (ed version only) for anyone with a valid uni/college email address. Someone else probably found it but, hey, I thought I'd post it here anyway.
Got AutoCad 2010, Ed. version, 64 bit. I picked 2010 because it's what I use in school, but I literally could have gotten everything they make, there's no apparent limit to number of programs. Pretty awesome break for an engineering student on a roughly $1000 program