Tivo, Inc sells a digital video recorder/personal video record device.
A brief mention of Tcl use at Tivo:
http://acmqueue.org/modules.php?name=Content&pa=printer_friendly&pid=53
". At TiVo the main public domain tool we use is the Tcl scripting language. TiVo developed a proprietary extension to Tcl for manipulating the database and media file system on the TCD."