Another "missing item" is toolbox.wolfram.com. There are many functions people write that would be amazing useful to others but will never be shared. I have shared some potential toolbox entries here like a function that receives evenly spaced time/data pairs and returns FFT in terms of Hz. Handy to have laying around. I started a Toolbox.nb that I refer to often. It would be great to have an "open source" sharing mechanism to have the community support each other. Some of the things in my toolbox:
1. Cool graphing functions with very simple legends 2. Canned functions for unique file formats 3. Easier ways to measure time than Timing 4. Database access routines 5. Initialization stuff 6. Functions to communicate over Ethernet 7. Functions to talk to external COTS test equipment
It would be cool to have a community place to store and share this stuff. Like a sourceforge model for Mathematica. Peer reviewed notebooks or external applications to extend Mathematica.