I'm with cyc. I've got 9 pylons in my backyard, strung along at 30 foot intervals. Every day it isn't raining, I find time to go and hit a some wedge shots, and note how far they fly.

It certainly came in handy on the weekend - I got up and down a few times more than I'm used to, and actually stuck a wedge to 2" (big ball mark) and rattled the stick! All from inside 100 yards.