Definitely cool, but then the neighborhood kids can't try to catch them (at least, not twice)
Good evening UP,
The balloon slingshot is nice, but at your advanced age, you really should go for something more like these:
http://www.youtube.com/watch?v=9...h?
v=90buminGzfw
http://www.youtube.com/watch?
v=3...feature=related
With the right engineering prof, you can add even more power. 
- Jeff
Commenting by HaloScan
