I've seen some small tent fans, but noting much more than that with the exception of mister/fan combos, but you wouldn?t' want to get the inside of your tent wet and turn it into a humid mess... then later the mold comes in when it gets stored unless you thoroughly dry it out...
The thing about most any type of air conditioning, as far as I know, is that they're heat exchangers, so one for a tent I would think, would have to have parts both inside and outside the tent.
There's also a weight issue there.
Not to mention that most tents aren't insulated at all, so any cooling is not going to last very long.
The best method to cool a tent is to keep it in the shade, and keep air moving through it.
Of course technology is always on the move. There could be something out there, that I have no idea about, and therefore I am making myself look like a complete *** right now. <img src="/images/graemlins/laugh.gif" alt="" />
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"Learn survival skills when your life doesn't depend on it."