OK, so you love being on your bike so much that you want to go everywhere and do all your errands and commuting on it. When you're in a car and you see someone on a bike you're annoyed it's not you. You feel sorry for the poor schmucks who are stuck in their cars. You want to see just how much cargo you can load onto your bike. Wait, what? If you want to do all you can by bike, that means you'll need to be able to carry groceries and general cargo safely and easily. I completely understand the woman from Seattle you may have read about last fall who tried to carry a mattress on her bicycle. I've carried a patio umbrella (attached to bike frame) and it's base, cross country skis (reminded me too much of jousting), and countless watermelons, not to mention cases of beer and large bags of dog food and even an electric piano. Without a trailer. I'm not going to discuss trailers today, though I've used one. They are wonderful and turn your bike into a minivan. I'm not going to discuss longtails, transporting children, touring or camping today either, those are topics for another time. Today I want to address simple trips to the store. While I do make dedicated trips for grocery shopping on occasion, usually I'll make a quick stop on the way home from a job. Since I work all over the city and my route to work is constantly changing, I need to be prepared for hauling cargo at any time.
I know many are loathe to attach anything to their bike, so the idea of a rack for attaching a trunk or panniers may not appeal to them. If you are one of these, a backpack may suffice. There are some made especially for bicycling, with improved load distribution, rigid frames and even air vents. However, back packs give you an unstable high center of gravity, stress your back and aren't much fun on a windy day. And then there are the sweaty backs. If you are commuting and not changing clothes, you really don't want that look when you arrive at work. Messenger bags are OK, I have one and I like it when I have lunch to carry and winter gear to take off and stow when I arrive. They can work for grocery overflow as well, though my go-to overflow bag is a backpack which was originally a front pack pet carrier I converted. It is capacious and has a padded rigid bottom and semi rigid mesh walls with top clasps. What works best in my experience however, are panniers. There are many different styles to suit your particular needs, from open top grocery panniers and insulated carriers, to garment bags, and more professional and stylish looks. The selection seems limitless.
Getting the weight off of your back and onto the bike is a relief. I know people with front and rear panniers so they can really load up. That's fine, just remember front panniers limit maneuverability. You may like the idea of a handlebar basket and really want to put your little dog in it `a la the Wizard of Oz. They make those too, just remember that very much weight in front baskets limits maneuverability as well.
I made my first set of panniers from a Frost Line kit when I was in college in the late 70's. I still have them, they only need new shock cords. Currently I use a 20+ year old expandable Jandd commuter bag that still has all it's zippers working. I've had to replace the shock cord and hook, and it's as punked out as possible by now. The inner bolts attached to the stiffener once destroyed a Jimmy Hendricks album I had packed next to them, but it still does it's job so I haven't replaced it yet. Besides, I think it's unlikely to get stolen off of my bike. I appreciate the outer pockets that organize my extra gear, such as rain cape, wind vest, pump, lock, light, nylon string bag for overflow, etc.. And since I'm often trying to load more on, an extra bungee cord and a carabiner are useful, too. When I'm out all day, I like having these things on hand. Besides, the added weight resistance only makes me stronger. Speaking of health, a University of Utrecht study shows that even short transport trips add 14 months to a cyclist's life span.