I'm reading Randall Munroe's book How To: Absurd Scientific Advice for Common Real-World Problems. I probably don't have to tell you this, but it's awesome (as is everything from Randall Munroe, the creator of xkcd comics). The whole idea of the book is to go use some crazy ideas to solve mostly common problems. One chapter focuses on how to cross a river. He gives you lots of options. You could change the course of the river or even evaporate all the water in the river (both ideas are silly and fun). Another option is to use a kite to get across the river. And here is the fun part—Munroe states that both a kite AND a balloon could extend over a river. As the wind speed increases, a kite gets higher in the sky. However a balloon gets lower as the wind increases.