[Phys-l] Software for drawing free-body diagrams?

[Bill Baggett <writebill1@gmail.com>]

What software exists to help students draw free-body diagrams?

I'm particularly interested in software that is:
     1) specialized for drawing free-body diagrams, and
     2) free (of course open source is ideal) or inexpensive.
However, if you feel that a particular general-purpose graphics
program is better than most for this task, then that would also be
good to know.

Thanks!
Bill