Lifted from UKPuzzle, here’s a thematic crossword with no clues:
http://crossword.info/anaxcrosswords/TheMissingXword
Please note this doesn’t have a PDF link.
Anaxcrosswords Crosswords by Anax / Loroso
Recent Comments
Anax on Taking The Plunge abikerideaday on Taking The Plunge 
i Cryptic Crossword… on Grid Balance Michael Lloyd-Jones on It’s been a while! Tony Collman on It’s been a while! Anax on It’s been a while! Tony Collman on It’s been a while! Anax on It’s been a while! Tony Collman on It’s been a while! Michael Lloyd-Jones on It’s been a while! kishoremrao on No Teacher! Hanni on Music hanni2 on It doesn’t matter Anax on It doesn’t matter Hanni on It doesn’t matter
Anaxcrosswords 
Got the idea behind this quite quickly, but was surprised how careful I had to be to find unique right answers to avoid having to rub things out.
[I don’t think that gives too much away …]