[quote author="keefaz"]I use Geda in Linux
http://www.geda.seul.org/
there is a Mac OSX version through fink:
http://www.ghz.cc/charles/fink/
But honestly I haven't tried it on Mac OSX
It is free, unlimited board size, up to 16 layers by default (can add more if wanted...), circuit simulation available etc...[/quote]
I was able to build the gEDA suite under OS X 10.4 but it went to shit when I installed 10.5.
There are some dependencies that make building it quite a challenge. The most significant is guile, which depends on the gmp library, and the gmp maintainer is quite hostile to the Mac and as such that library does not compile without intervention (./configure; make fails). Apparently, other developers have submitted patches for gmp to allow it to build on OS X but these patches have been rejected.
That's the sort of rank stupidity that makes it difficult to recommend open-source software to anyone who's not a serious Unix hacker.
But back to gEDA and pcb ... there are a handful of annoyances that make it less desirable to use than alternatives. One is that when you drag a footprint, the ratsnest doesn't stay with the footprint. You have to drop the footprint and then the ratsnest is regenerated. Also, many decent PCB tools will show the netname on each pin; pcb does not do this (and the developers don't see why it's useful).
I follow the gEDA user mailing list and the suite is in active development, which is a good sign. There's a lot of discussion now about different approaches to libraries and every user has an opinion!
McCAD looks interesting but I wish they'd update the user interface ... it's so OS 9. It really needs a refresh.
-a