A pelt could give a great increase in above ambient temps. You need to keep any temps above the dew point of air (point where water drops out of the air). A simple circuit could do this with ease.
There was a cpu cooler that did this (
http://www.silentpcreview.com/article155-page4.html). If you were attempting to this, buying that and then attaching a cooling kit might be the best option. Either way using the circuitry on that could be very useful. You are still going to be very very careful though.
The 28c is probably a little high. If you used a dehumidifier in the same room, very low temps should be possible but it would need some hacking.