Bike Post: How do you carry stuff?

Yuba Mundo

I'm in the market for a new bike and I've pretty much made up my mind to make it the one above, the Yuba Mundo. I'd love to be able to easily tote around people and things on a whim. I'm interested to see if anyone else here uses a cargo bike or if you don't have a cargo bike, per se, maybe just what systems work for you to carry stuff.

Regarding the Mundo: I like it because it the rear rack is built into the frame and its supposed to be able to carry 400 lbs. in addition to the rider. It's got nifty looking accessories like a front rack that mounts on the frame instead of the fork to keep the steering light. Also, handlebars can be mounted on seat post, so another adult can hop on the back easily for a ride.

So, how do you carry stuff on your bike?