How small is the smallest air conditioner?

Question:I'd like a small, lightweight, cheap, and quiet air conditioner that blows cold air out of a hose. It just has to be enough to keep my sleeping bag cool.

Answers:
I have been in the HVAC business for 25 years and have never heard of anything like this. There are several problems with it. One compressors and electric motors are heavy, even small ones. Second I assume since you mention a sleeping bag it would be carried with you somewhere. Compressor motors require alternating current so you would have to plug it in and to a fairly large circuit. There are no battery operated compressors made in commercially available AC equipment.