I wrote a small Python program called timeshow to do timed, randomized slideshows for gesture-drawing and similar drawing practice on a desktop computer. This can be handy if you've downloaded art image packs and aren't online or otherwise can't use the Proko timer tool. You do need to have Python installed on your system and be comfortable running a program from the terminal / command-prompt, but other than that it's simple and easy to use. You can run a slideshow from all images in a directory (including optional search of subfolders), or from a text file with a list of file paths or URLs. https://github.com/ccorbell/timeshow