MING
“The MD-Energy Minimizer Of Knots”
http://www.math.uiowa.edu/~wu/ming/ming.html
ming-linux.patch.gz: patch to compile with g++
also interesting, is MIN, “The Earlier Version Of MING”
http://www.math.uiowa.edu/~wu/min/min.html
non graphical version of the energy minimser code that supposedly compiles on unix, although i suspect it will need similar massaging as above to compile with g++. may be useful for study.