Already have a fairly large 20" box fan, so bought 8 cheap and
cheerful hand towels, wet them well and hung each one over a hanger in
front of the fan, with a gap of 2" in between.

Noted that the side nearest the fan dries quickest, so doubled up a
third of the towel on this side (so half with two layers, half with
one)

Also noted that the best cooling is had when the towels are quite damp
but not wringing wet.

Anyway, got an air temp of 26°C coming out of the cooler vs. a room
temp of 34°C, so quite nice when sitting in front of it. Room humidity
wasn't changed much at 45-50%.

Also bought a cheap pump sprayer to keep the towels damp, looks like
spraying the tops every 30 mins with half a litre of water works well
without them getting dripping wet.

Tomorrow might make a frame of strip wood to hang the towels on and so
keeps each side 1" apart to double the number of layers. Also under
consideration is making a 'tray' of thick polythene with rows of very
small perforations to make it easier to keep the towels damp.

Currently giving 23°C vs a room temp of 30°C so will have to turn off
soon as am getting a bit chilly!

So, if you have a large fan and need some extra cooling it might be
worth a try... Even putting damp laundry on an airer and blowing air
though it should lower the air temperature some way.

cheers,
Pete.