Need ideas for a Man Up destination trip

Every year, buddies and I get together for an adventure trip, doing things that sane people only do when they're coaxed into it by other friends. "I'll do it if you'll do it..."

This year, we're thinking about whitewater kayaking. Most of us have done WW rafting (Gauley, Tuolomne) and sea kayaking, but no whitewater river kayaking.

Can you guys offer some recommendations on destinations? We want to do something that's far more exciting than a run-of-the-mill experience for urban weekend...

Need ideas for a Man Up destination trip