Z88 is a compact Finite Elements Analysis Program (Freeware)

The new version Z88 13.0 for UNIX, LINUX, Mac OS X and Windows is GNU GPL Freeware.
Z88 is handcoded using pure ANSI-C and the true Windows API or GTK+ calls.

http://www.z88.uni-bayreuth.de/z88v13/english.html

Native 32-Bit und 64-Bit versions for both Windows and LINUX/UNIX