Ray,
I'm using a Supermicro (take a look at my sig).
VERY pleased with it. IPMI is sooooooo useful and is very easy to set up. Useful not just for the remote access to the console but for powering down, switching back on, and attaching a virtual device (ISO image). This is something I personally have not used, however, does not get mentioned much and I would imagine "could" be useful for some people. I use something similar in VMWare and being able to attach an ISO image (I don't have a locally attached CD-ROM/DVD-ROM) is the dogs danglies.