Athena is a simulation application written in TCL/TK; it models the actions of political, economic, and military actors in a war-torn region, and the effects of those actions on the local civilians. It was developed at the Jet Propulsion Laboratory by WHD (among others) and has now been open sourced under a BSD license. In addition to the simulation code proper, the project includes a considerable amount of infrastructure code, much of which has been presented by WHD at the Tcl Conference over the years. See especially the "marsutil" and "marsgui" packages in the mars repository.aspect is very excited to see this code put online! Some nice examples of snidgets (and broader use of snit) in there that I'll immediately adopt (*cough* tklib), and the Dynaforms code I've been wanting to look at since seeing the video of your talk at Twentieth Annual Tcl/Tk Conference (2013). Thanks Will and thanks JPL!WHD Thank you! Take a look at the "field(i)" man page; it explains the standards followed by the widgets we use as fields in data entry forms. The matching "field" widgets in marsgui all follow it.