I like alrik's suggestion on exotic weapon types, here's one more:
[url= http://en.wikipedia.org/wiki/Urumi][/url]

basically a steel bladed whip, can be disguised as a belt... not very effective against metal armor, but could be used to knockdown), but will rip large groups of fleshy foes into shreds in a single attack.... could have high dex/perception requirement to use properly.


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