If you have several machines, you need a queueing system to ensure you are maximising your throughput of jobs. We recommend Sun's Grid Engine.
We have created our own framework for submitting simulation jobs to the queue and presenting the results.
As fast as a commercial simulator and free: Verilator is a cycle based simulator which works by translating Verilog to C++. Ideal for regressions.
Covered is a code coverage tool that post processes waveform files. No change to your simulation flow, no simulation slowdown.
Gtkwave waveform viewer.
Still using CVS? Subversion is better, and faster. So similar to CVS it will be second nature to use, but with changeset support and without the CVS annoyances.
We love Trac. Subversion web interface, wiki, bug tracking system in one. All smoothly integrated. Perfect.