Don't peek! PDF Answer
To help construct themed crosswords, I wrote a simplified constraint-satisfaction algorithm. 'Cryptics', as you Yanks call them, are the present target since they appeal to my twisted mind: modifying the system for US-style puzzles might work but is up to someone else, not CryptoBoy.
Warning: In the first two efforts, words can come from idiosyncratic and unique aspects of Off Monroe Players (back to main hobby page for more on them), and can include references to all the Gilbert and Sullivan shows as well as spinoffs like Gayden Wren's "G&S Christmas Carol". Third effort is more generic. The report describes the work, all code, examples, etc. pointed to in links below.