"The Apple Mac mini has been around in one form or another for almost three years, and while the internal components have changed, the general concept and overall design has stayed the same. Pricing starts at $599, but the one we looked at is the upgraded 2-GHz $799 model. It's one of the forerunners of the green PC, having gone through several generations of substituting energy-efficient notebook-class components for desktop parts since the G4-powered Mac minis of early 2005. The Mac mini has been the lower-priced, entry-level Mac, but now that it's equipped with the Core 2 Duo processors, it is as powerful as a larger desktop while retaining its power (and space) savings. The Apple Mac mini appeals to both space-constrained and green-thinking PC users".

Domingo goes on to comment that the mini is quiet and energy friendly when he states:

"Like most Apple systems the mini is quiet, with almost no fan noise. (You have to stick your ear next to the mini to hear the hard drive working.). It does still use an external power brick, but now that's a plus instead of a hindrance. That's because the brick is more efficient than some internal power supplies, particularly when the system is sleeping or idle. This Mac mini is both Energy Star 4.0 and EPEAT Silver certified, so it will serve you well while making a minimal impact on the environment"

The Mac mini just like other Intel-based Macs can run both Mac OS X and Windows.  Domingo states:
"Compared with systems like the HP Slimline 3200 series, the Mac mini is much smaller and has the benefit of being both a Mac OS X and a Windows PC."

The review concludes with the following:
"The Apple Mac mini continues to be an energy-efficient computer as well as a design statement. It's an attractive alternative to Windows Vista PCs, even those with small form factors, since it's a visual, technological, and spiritual match for the iPods in millions of pockets worldwide. It's worth putting on your short list"

You can read the review in full here.