For all the teachers, home schoolers, parents, summer camp counselors, and people who want to practice vocabulary, there's a very cool, free, small, and easy to use program for Windows machines called Eclipse Crossword. Manual install download link.
You create word lists with the program, then it randomly generates puzzle grids and prints them to the default Windows printer. If you have PDF creating printer drivers, you can them manipulate the end product that way, or within Eclipse, you can save the puzzles as graphics and put them into your word processor or page layout program of choice.
Enjoy!