Perhaps not the right section but I figure most of GBAtemp's 3d modelling crowd knock around here and they probably outweigh those that use CAD for engineering type reasons (electrical engineering aside). http://labs.autodesk.com/technologies/fusion 555 megs download, about the same installed (program files anyway, user directories seem less than 100 but it has entries in all of main places there). Should be free until the end of March unless you run the mac version (not so much big boy CAD in mac these days) in which case forever. Spent the last few hours messing around with it.... it takes an awful lot to get me interested in CAD these days (especially autodesk stuff) but their claim that it "Unites direct and parametric modeling workflows" is pretty spot on- for me it feels like the old VRML editors but with the abilities of a proper CAD program (make a cylinder- click on the edge and up springs a fillet or chamfer or custom option) with a few nice modern touches (proper radial menus, have a play with the cube on the top right of the screen). Seems to support saving to a whole bunch of formats as well (I am several years out of autodesk but that would be a first for me) including STL and at least part of main rival pro/engineer (my usual option for parametric modelling if the likes of BRL cad or just doing it 2d with multiple views does not cut it). My only real complaint is lack of physics testing (zebra testing, nice sectioning and interference is there mind you) but as that is usually a fairly pricey extra and this looks like a "prosumer" program I can not really complain. I still have to test out the potential for engineering diagrams but I expect something halfway acceptable there (no prominent options that I can see though). Naturally a proper test will take a couple of weeks and I do not have dual monitors set up right now so no comment there not to mention I will have to learn all the shortcuts/set up my mouse properly for it. However I think I might have to invest when the time comes which is a shock but not as much as my actually quite liking a CAD program from a usability standpoint. Short version- the fully featured demo is free and if this does not make a big dent in the CAD world I will be stunned so maybe worth spending the time to get this down now if it is the sort of thing you do.