You could try and make a DIY swamp cooler? There’s lots of instructions online for how to make them, and basically the only consumable is water. The only caveat is that they work by drawing hot air in from an open window to evaporate water, so it’s not very effective in high humidity or low temperatures.

I think it’s Gen 6 (PS2/Xbox). But at the time the Gen 6 consoles were new, the Gen 3 that you consider retro was about 20 years old, just like these consoles are now. I think they still fit the label of retro pretty well, but it’s always hard to consider something newer than your childhood as “old” tbh