A program I wrote to take the tedium out of those damn puzzles (i.e. cheat). Will solve most easy and medium 9x9 puzzles on its own, and greatly assists with harder ones.
Instructions
Start by entering the numbers supplied in the puzzle.
Do this carefully as mistakes cannot always be undone. You can use the "save position" button periodically to save your progress.
You should see the puzzle begin to solve bits of itself at some point. Simply let it run until it comes to a stop and continue to enter numbers.
The small grey numbers represent the possible solutions in the unsolved boxes.
If the puzzle does not completely solve itself, you need to give it a bit of help.
You can either solve a few numbers using logic to get it going again, or you can do some trial and error:
Save the position, then find a square with only two possibilites and choose one at random. Continue to do this until the puzzle is either solved or clearly wrong, using the restore position function to try the different possibilities.