Wei-Hwa's Puzzle Module for July 28th, 2006
Addendum (2006-08-04): These puzzles came out much harder than I had originally intended, but unfortunately I only had a few days of development time before I was off to the IPP.
Addendum (2006-08-10): Hastened develop time has its costs. There was a bug in the released version that made it so that you couldn't drag the numbers into the grid correctly if you changed puzzles (although the keyboard shortcuts still worked, and you could drag the numbers back. I've fixed it now, although you may need to clear your cache.