TCP Monitoring

A nice TCP Monitoring application. You can download the debugger from http://www.itsamples.com/software/tcp.html

Datamodeling tool

"Toad Data Modeller" is a very nice ER tool. you can generate SQL scripts as well to generate your database.

Opensource Project Management tool

openproj is an opensource project management tool. It has most of the MSProject features at no cost.

Another opensource project management system is gnome planner.

Another project management tool is openworkbench.