temperature controlled pc fan

["Paul Robinson" <ukcueman@xxxxxxxxxxx>]

My node zero is in the loft. On the hottest days, it's too hot in there for
anything to
work reliably. So I have a rack which has a PC fan installed in the back,
with a duct to
the soffet where I hope (once it's running) it will be able to pull in
sufficiently cool
air to keep the air in the rack cool enough. What I'd like to do now is to
have this
switched so it's either on only when the temperature is above some
threshold, or so that
the speed changes with the temperature.

I've found a suitable kit on maplin's (http://tinyurl.com/yt4yc) for on/off
control, and a
circuit for speed control (http://www.overclockers.com.au/techstuff/a_thermalfans/),
but
does anybody know of a product in non-kit form so I can leave the soldering
iron in its
box?

Thanks,
Paul