First Sudoku Solver, in a chrome extension. Quick with easy puzzles, slow with harder ones.
Easy
0 0 0 2 6 0 7 0 1
6 8 0 0 7 0 0 9 0
1 9 0 0 0 4 5 0 0
8 2 0 1 0 0 0 4 0
0 0 4 6 0 2 9 0 0
0 5 0 0 0 3 0 2 8
0 0 9 3 0 0 0 7 4
0 4 0 0 5 0 0 3 6
7 0 3 0 1 8 0 0 0
Time: 109 milliseconds
Hard
0 2 0 0 0 0 0 0 0
0 0 0 6 0 0 0 0 3
0 7 4 0 8 0 0 0 0
0 0 0 0 0 3 0 0 2
0 8 0 0 4 0 0 1 0
6 0 0 5 0 0 0 0 0
0 0 0 0 1 0 7 8 0
5 0 0 0 0 9 0 0 0
0 0 0 0 0 0 0 4 0
Time: 291.0219 seconds
4.85 minutes