Img is a collection of format handlers for the Tk photo image type.
Earth orbits and satellite coverage display in 3D on your laptop.
Doing 3D with Tcl
Open Source Solid Modeling CAD
A C extension to Tk that provides functionality to modify images
Bulk Downloader for selectable Images (even Google Images)
Image viewer for animated GIFs
A Tcl/Tk widget for OpenGL rendering.