What I'd like to encourage people to do here is list favorite applications and extensions built around Tcl.
What do you find yourself either using the most frequently, or using to show someone what Tcl can do?
LV: Of course, number one has to be this wikit.
I really love tkinspect and I find myself most frequently using either eskil or frink when developing.
I also love the functionality in teacup.
I just looked through the code in my ~/bin directories. Most of it is code from this wiki or from the community- the rest are things I've hacked together over the years.
The most common packages used in the various apps are: Tk, http, log, various struct modules, htmlparse, log, Tclx, oratcl, base64, csv, metakit, thread, Tnm, Trf, admin, auth, cgi, cmdline, mail, mtype, scripdoc, session, starkit, as well as a lot of "one time use" type modules.
RS loves most to demonstrate things in an interactive console, up to tdom: my visitors (colleagues) are mostly very impressed how simple it all is, and I then mail them the sample code to use in their scripts :^)
JM I frequently use tclodbc, BLT and TableList. I am a fan of RS's whizzlets