This powerful but cheap ($45) air cooler is made from:

1 x Heater core (from any auto wrecker/car parts shop)
1 x High power computer fan (from eBay)
1 x Bilge pump (from eBay or any boat shop)

The cooler actually works well and is powerful enough to work in a hot car in the sun but you’ll need to use very cold water. Freeze lots of ice, and refrigerate lots of water.

If you can get the water temperature below 10°C / 50°F then you’ll be smiling all the way to your destination without drowning in sweat.

For use in an office, just use cold water from the faucet.