Replacement computer options/ideas?

[joe at actionline.com]

Last Friday, my main computer crashed -- a victim of overheating.

Apparently, I had a few warning signs over the past few days that I did
not recognize as such.  The keyboard would quit working with the last two
of the three lights labeled "1" - "A" - "(down-arrow)" on the upper right
corner of the keyboard blinking.  The first light "1" was lit when the
numlock key was on, but I never did know what the other two lights were
for.

In any case, the only way I found to restore the keyboard was to reboot.
I should have posted a note to PLUG about this, and perhaps could have
avoided the crash/disaster.  But ... oh well ... c'est la vie.

Fortunately, the hard drives are okay and my data is safe.

But now the question arises, what to get as a replacement computer.

The box that failed had a 750-watt power supply (seems rather excessive).

As a temporary measure, I bought a little HP mini-tower off of Craig's
list for $175 (1 gig ram, 175-gig hd) on which I've installed the newest
version (10.1) of my distro of choice: PCLinuxOS.  It is very fast and
runs very cool, I think because it has a very low-wattage power supply. 
I'm actually setting this up as a small desk unit for my wife to replace
her old windows box that she rarely uses any more since I got her an IBM
Thinkpad running PCLinux. She now likes Linux better ... yes!

So, after all that too-long-winded explanation ... back to the original
question.  I'm looking for ideas/suggestions for a replacement desk unit.
I don't see any need for the latest and greatest high-powered unit.  I
just want strong, reliable, low-heat, low-power consumption (I think).

So what does the collective PLUG wisdom suggest?