I really think we shouldn't be relying on someone donating a fan, when they are pretty essential in summer. Usually this 'donation' is one of us getting pissed off and going down the shop to buy one (which I did last year). I think a little common sense has to prevail and say that just because its a bit cooler now, doesn't mean we won't need them again next year, so we should keep them around. Besides, its not like a few fans around are gunna take up a huge ammount of room.
We should probably keep a good supply at the space, probably 4 - 5 at least, reasons are numerous, to keep us hackers cool. They can be used for cool smoke effects if we ever need them, and also if global warming suddenly takes a turn for the worse, and we end up with a december day in the mid 30's, we'll be happy we kept them