How many machines is enough? I think, one :-)

Interesting post.
I have seen people keeping around a lot of machines. For me, multiple
machines produces too much noise :-(. I personally have been trying to
keep a single machine + laptop. Usually at the end of the product cycle
(such as now) I have to maintain two machines since closer to release
code base forks and RC branch only gets selected fixes while active
development continues in the branch that goes towards the next release.

I don't need separate test machine since our team employs dedicated
check in / test machine. I run a subset of tests on my primary machine
(it takes about 30 minutes), then obtain a cookie on the team checkin
machine (also called 'buddy build machine'), submit changes and then
run build and tests on the shared machine via terminal server (takes
about 3 hours). If everything goes well, I release the machine and
release script automatically updates 'safe sync' label to my change
list.

I run Windows 2003 Standard Server on my primary box. Server is more
convenient since I can open terminal server session to my own machine
and run tests in that session while continue working on the primary
console.