.... cool, after a quick run of the examples, my thoughts:

... at least add bezier lines, like is shown in most gui demos

... i like the way you can transfer the geometric data across canvases....people have been looking for a good way to do this for awhile.... so you can have "shared drawing whiteboards" across sockets.....

... other features?.... yes, besides socket_abilty :-), people also want to save what they have done..... it would be nice the data to a file, and be able to reload it later

.... i'm sure i'll think up something later ..... like oh yeah... an eraser function for the lines....if you need a quick idea of the data you would have to save for an eraser to work on a smoothed line curve....see ztk-roller-coaster-simulation