Hmm hoplite ish builds come to mind.
How about a bamboo spear wielding, one slot shield using hoplite build with a shortened spear as a secondary weapon? Rare enough and still very effective, especially with all the cav around lately.
Or go for a mounted thrower. Not many of those around. Wouldn't it be cool (and useless) to run around on horseback chucking axes at people whilst doing a drive-by? Also a good anti-cav class if you use javelins or throwing spears...
If that's not rare or unique enough: make a full tincan strength build mallet guy and let him ride around on a stumpter for movement. Maybe a 30/6 build? Take 2 shield to stay alive whilst riding / walking.
Ofcourse, you can always do some high athletics, high weapon mastery shielder build and use a flanged mace and dance around and spam people.
I also like the fake peasant suggestion, but it's been done too often.
