Okay, so the title was meant to catch your eye. And if you are riding a bike then you don't have a trunk. Where do you put your stuff when you commute by bike?

My friends from Portland who visited me over the winter break raved about her XtraCycle. She loves, loves, LOVES it for hauling two kids and a bunch of books or groceries:

I used the cheaper TransIt panniers for awhile, but the hooks pulled away from the bag over time:

Looking for a sturdier bag, I became smitten with an Arkel pannier. It was hard to justify spending so much  for a bike bag until I convinced myself that it is way less expensive than a car and will last a long, long time. My Arkel has been worth every penny. It is super functional and perfect for an urban work commute.

http://www.ecovelo.info/2009/05/09/arkel-metropolitan-pannier/

A friend working at UCLA  bought a colorful and fun pannier:

http://detours.us/product_info.php?cPath=44&products_id=252

Of course, messenger bags remain ever popular:

And for the purely functional, no frills approach, let's not forget the milk crate:

http://www.chicagobikeblog.com/2007/08/milk-crate.html

What do you use to lug your stuff when you are riding a bike?  Share your stories and images in the comments!