http://woodgears.ca/eyeball/
Mine, on third go:
Parallelogram 2.0 2.8 4.1
Midpoint 3.2 2.0 11.7
Bisect angle 8.1 8.2 1.9
Triangle center 0.9 6.2 1.2
Circle center 4.2 1.0 2.2
Right angle 2.5 5.7 5.9
Convergence 2.2 5.0 4.0
Average error: 4.05 (lower is better)
Me far nearer a perfect 10. :(
Your inaccuracy by category:
Parallelogram 2.8 3.2 13.0
Midpoint 13.4 2.2 3.6
Bisect angle 4.0 1.2 2.6
Triangle center 1.4 2.1 8.0
Circle center 2.8 2.2 3.2
Right angle 1.5 0.7 2.1
Convergence 1.0 1.0 1.0
Average error: 3.48 (lower is better)
Parallelogram 1.0 2.2 1.0
Midpoint 6.4 2.0 6.0
Bisect angle 2.4 3.6 2.0
Triangle center 6.9 7.0 6.2
Circle center 4.2 9.1 2.0
Right angle 0.5 0.2 1.0
Convergence 5.7 2.0 5.4
Average error: 3.66 (lower is better)