It had been a long time since I've seen any sign of life from MapServer's Tcl bindings, but recently I've been corresponding with a developer of the FlightAware site about enhancements to mapscript for use with their live flight tracking application. See the page for KDEN, and click on the map in the right hand pane to see Tcl and MapServer in action. That's a great looking map; I love the nocturnal blue background with lighter blue and green vectors and annotation. You just can't do this kind of unique, old-school, presentation with the Google or Yahoo map APIs.
Also created with Tcl and mapscript are frames of this animation. I lost count of how many different holding patterns this plane was given.