I'm currently using a "swamp cooler" to regulate my fermentation temperature for the first time, and it is working surprisingly well. I'm giving this a shot in the hopes of eliminating some off flavors that all of my beers so far have been exhibiting and that I suspect is due to making the yeast "sweat" (i.e. straining the yeast by fermenting at higher-than-recommended temperatures). I started simply by immersing the brew pail about three-fourths of the way up in two store-bought bags worth of ice water in a storage container. The water temperature hovered around 32º for several hours but, after about 24 hours, rose to about 70º. I added a 2L bottle of frozen water at that point, which dropped the temperature back down to about 60º. Over nearly three days, the temperature slowly rose to just under 70º at which time I added a new frozen bottle. I'll continue this process of monitoring the temperature and swapping frozen bottles throughout the primary and secondary fermentations.