http://woodgears.ca/eyeball/
The Eyeballing Game.
Basically you see how accurately you can position points only using your eyesight.
Your inaccuracy by category:
Parallelogram___105.8__4.5__3.0
Midpoint_______7.0____14.3_7.3
Bisect angle____6.5____0.9__0.5
Triangle center_63.0___14.8_5.7
Circle center___3.6____0.0__2.0
Right angle____2.7_____0.4_10.2
Convergence___4.1____6.0__7.2
Average error: 12.83 (lower is better)
lol, i forgot what paralellogram was (i thought it was a rhombas) and i thought on the triangle one i was suppose to find the spot that makes each distance from each point.