I'm relatively new to Tcl. I like its cross-platform compatibility and "stringiness," but the real "killer app" of the language for me is its ability to be glued into other apps.

Tcl projects:

• GPIB-Tcl http://gpib-tcl.sourceforge.net for controlling IEEE-488 equipment from Tcl.
• Pets 411 http://pets411.sourceforge.net for creating simple animal rescue databases to export via XSLT to Web sites or to animal-oriented search engines.

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