Version 2 of Where can I store my nifty new Tcl program so others can get it

Purpose: Outline for people new to the community what resources are available for sharing their Tcl related code, documentation, etc.

http://www.tcl.tk/software/ (the semi-official Tcl home) has a list of software and extensions for or using Tcl.
http://sourceforge.net/ is available for Open Source projects
ftp://ftp.procplace.com/pub/tcl/ has been available for quite a long time.
The Tcler's Wiki, this site, is well known for web pages with small application source code.

Add additional references as you find them.