[_ck_]

Some bbPress forums with unusual designs:

http://www.youlookfab.com/welookfab/

http://www.zanzibar19.com/forums/

http://cairoshell.com/forum/

http://forums.astateofmind.eu/

http://forum.3oneseven.com/

http://mybabyourbaby.com/forums/

http://www.adityanaik.com/forums/

http://www.doncastergamers.co.uk/forum/

(more to be added later)