One thing people suggest if you do not have/cannot afford some electrical fermentation chamber is the swamp cooler. A simple construction, you place your fermenter in a water bath, throw a shirt or towel over it to create a wick for the water to rise up, and then you throw a fan blowing on it. The moving air will cool against the water on the shirt and blow cold air against the fermenter, cooling it. The problem with this method is that you have to burn a lot of electricity operating the fan all the time and in humid climates, like Texas, the swamp cooler is less effective. (It relies on evaporation but evaporation doesn't occur when the air is already saturated with moisture. So instead of cooling your fermenter you just blow around humidity.)
In the alternative, you can toss the fermenter in a water bath and add ice packs or (plastic) bottles of frozen water and change out the bottles/ice packs throughout the day. You can also toss a fan on it to blow hot air away from the water and fermenter. Personally I do this strategy, especially on smaller batches because it usually only requires switching out the bottles 2-3 times in a 24 hour period. The major downside is that you get temperature swings as the water cools the fermenter very fast when you add the ice and then warms up over time up until you add more ice. It works well on more forgiving yeast strains but for temperature sensitive strains, such as weizen strains, it can really mess up your flavor profile. Also, if you don't change out the bottles/ice packs frequently enough your beer will reach into temperatures beyond what you really want in a beer.
Depending on how warm you keep your home during the day, you may be able to get away with brewing beer styles that appreciate warmer weather. This typically includes Belgian abbey/trappist/saison/wit styles where some strains actually benefit from warmer weather. Many of these strains produce desireable esters in the upper 70s to low 80s. So that's definitely an option. If you can get the wort down to the mid-upper 60s when you pitch and let it rise to ambient temperatures, that can really help your beer get desireable esters in palatable amounts without getting a lot of off flavors from fermenting too warm.
Something to think about is that your beer really only needs to be kept in the 60s or low 70s during primary fermentation, so typically the first 3-4 days. After that you can pretty much let it go to ambient temperatures once fermentation ends and the yeasts are doing clean up. Of course, a bigger beer is going to take longer so you'll need to adjust for your beer's needs.
That brings up another subject. A lower ABV beer is more likely to produce fermentation quicker and at a cooler temperature than a big beer, so not only will you need to worry about running a fan or switching ice bottles or whatever for fewer days but you produce an easier environment for the yeast to work, which will help reduce the likelihood of off flavors. (In bigger beers the high sugar and then high alcohol environment puts pressure on the yeast to perform, resulting in a greater likelihood of producing off flavors due to the stress.)
To keep riding that train of thought, it may even be beneficial to look at brewing your summer and fall beers at the end of spring and allow them to age into and through the summer so during those hot summer months you can kick back and enjoy some beer while you swim, BBQ, etc. You could spend May filling all your fermenters and drain them out into bottles as the summer progresses. That's most likely the easiest route to take (for those of us without the fermentation chambers).
Last summer I brewed some great beers in the cooler June and only threw down a couple big Belgians in the mid-late summer. As it was, I found it really difficult to keep those June beers cool enough and ended up accidentally knocking my wife's phone off the sofa into the ice bath. That was a pricey mishap. This summer, I haven't brewed anything at all. It's been incredibly hot and I've been gone 11-12 hours a day at an internship so I don't have any way to keep the beer cool. As much as I really want to brew up the watermelon wheat for the summer, I don't want to let it go to 80F during the day and end up with that nasty bubblegum taste wheat strains get when they ferment too warmly. And since a fruit beer will ferment twice, that's a lot of time to create bubblegum juice. I'll probably do it later in the summer when my internship ends and I am back to studying at home all day.
I also haven't been brewing because I just bottled 5 gallon of oud bruin which brings my total reserve of beer at home to close to 25 gallons. I have beers that are over a year old that I need to drink up to make room for new beers. That doesn't even include the 7 gallons of sour beer I have sitting in fermenters right now. (6 gallons of lambic, 1 of my brett-saison Christmas beer.) Some of those beers, like the two big Belgians, the cherry wheat sour, the oud bruin, the wheat wine and the scotch ale are fine to age and continue to improve, but the handful of bottles left of various session beers need to be finished off. So until I'm able to trim down my beer supply (it has taken over a LOT of the house!) I won't be doing too much brewing. I have about 9 gallons of beer waiting to be brewed up that I already have the grains for and that will probably be all my brewing until I get out to refilling the lambic solera in December. So not too much brewing for me this year. However, I'll probably do some test runs on some longer aged brews -- maybe another mead or cider -- just to keep something in the fermenter without having to produce more bottles of beer.