There is Phil, the free crossword maker http://www.keiranking.com/apps/phil/ but I haven't had the best luck with its automated fill. Lately I've been using Crossfire http://beekeeperlabs.com/crossfire/ to make puzzles and its auto fill is quite versatile, even if some of the choices can be iffy (but easily fixed with some manual tweaking). You can even provide your own custom dictionary for it to use in the fill.
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There is Phil, the free crossword maker http://www.keiranking.com/apps/phil/ but I haven't had the best luck with its automated fill. Lately I've been using Crossfire http://beekeeperlabs.com/crossfire/ to make puzzles and its auto fill is quite versatile, even if some of the choices can be iffy (but easily fixed with some manual tweaking). You can even provide your own custom dictionary for it to use in the fill.
The Phil auto-fill button doesn't do anything for me. Crossfire looks like it has this feature though, and it's probably a lot faster than mine