I bought a Kill-A-Watt recently and went crazy measuring everything around my house from CFLs, to fans. I found out that a small desk-fan running at its low setting consumes roughly 25W. That's 25W*0.001kW*24hours*7days*4.5weeks*0.07$/kwH==0.1323$/month to run all day all month. That's pretty cheap when compared to…