Simple and intuitive 2D vector drawing for electronics and not only.
Pencil2D is a cross-platform animation/drawing application.
Madeline 2.0 Pedigree Drawing Engine (PDE)
ARO helps physically disabled students to create mathematical drawings
2 players drawing program
A drawer for origami crease pattern
A Pixel Art style drawing program
OBSOLETE; try http://drawpile.net/ instead!