It is so funny you should ask, I spent over a week looking for the answer to this. I'm currently using a combination of a chest freezer and a Johnson Controls temperature controller (from Northern Brewer) and I have been able to control the temperature of my fermentations down to 1/2 a degree. It' awesome... The last bit of fermentation of 6 gallons of basswood traditional is taking place in it right now.
Here is the problem with finding a chest freezer, they're all too tall and way to narrow. Period.
After searching for a week I finally gave up, none of them were wide enough for my wide wine kit fermenting bucket or even a 6 gallon carboy. And the ones that happened to be wide enough, had too large a compressor hump, or "step". Then, in a last ditch attempt, I took a reluctant ride over to walmart. Carrying a measuring tape and a box cutter, and without knowing if they would even sell an item that large, I went searching through the home ec. department and alas, there it lay. A chest freezer with the perfect dimensions for both fermenters of all kinds and carboys of all sizes alike. It was humblingly beautiful, weeks of searching and there it was.
Unfortunately I'm typing this with
An Ipod and can't post my pictures untill the a.m. I will post up the pics and the model in the morning, it is truly a godsend amomg all chest freezers.