Here's my entry:
[url]http://users.on.net/~kachizmu/Sudoku.zip[/url]
Syntax is Sudoku.exe
Hope this is enough to get everyone inspired to have a go. This is a simple a brute force method, unoptimized (as there's little point, seeing as a better algorithm would be so much faster). Only works for order 3 puzzles though.
I haven't seen it crash yet, but it might - no guarantees!
Written in C - I've included the source and some example puzzles to play with.
Good luck everyone!
Well that kinda fizzled....
Cheers redwyre for the idea - I thought it seemed like a pretty decent challenge. Bit of a shame not to see more entries, but I'm guessing everybody must be too busy doing "real" code.