http://adohaha.github.io/uprosc_gcode A gcode simplifier for grbl (as there are some problems where precision is too high)
http://mymodelrobot.appspot.com A visualizer for URDFs (unified robot description format), used in ROS
https://adohaha.github.io/DH2URDF Denavit-Hartenberg to URDF converter
My main blog is available at www.gentle.pl (mainly written in Polish).