server room environment monitoring solutions?

 I've been authorized to replace the home-brewed thermal monitoring system for one of the server rooms I use at work.  I haven't done any research into this since building http://ssli.ee.washington.edu/people/nomad/thermalcube/ 10 or so years ago.

So I turn to you to ask: What's the current hotness in inexpensive environment (mostly thermal) monitoring solutions?