These panniers are waterproof and they hold a bunch of stuff.

Of course, I may have been smoking something during the installation process, which might explain why the one marked 'R' is on the left, and the one marked 'L' is on the right. But in any event, these Tidy Cat buckets are perfect. I have several bikes with racks, and when I want to use another bike, I just pull the buckets off of one bike, and quickly attach them to another bike.