Over the year, I have commuted from 20+ to 10 miles RT, and lately I have shifted from a typical road bike to something much more like a self contained touring rig (LHT, 38mm tires, front and rear racks). I carry about the same as others who have posted - my tools, spare tube, and patch kit reside in an under seat bag, and the clothes, toiletries, and chow go in panniers, front or rear as the load requires. I have found that I like to leave the panniers on the bike. Therefore I pack up my cargo in thin nylon sacks which I can easily remove from the panniers - this also helps keep the contents dry. One thing I always carry is a small first aid kit. It ia nor used routinely, but when it is needed, it is needed.

I think those who have pointed out the need for flexibility and versatility are absolutely correct. The one thing that apparently hasn't been mentioned is the need for superior visibility. Even if you don't wish to, sooner or later you will be riding in the rain, snow, and or dark. I would emphasize side reflectors, brilliant, if not gaudy paint jobs, spoke lights, and anything else that would make the bike commuter more obvious. I commute with two headlamps, one on my handlebars and one on my helmet. This winter I will be increasing my side and rear visibility.

I disagee with many here about the need for fenders. My experience is that road splash from passing cars gets me far wetter than the stuff thrown up by my tires, but my racks block some of the tire fluid. More and more, I tend not to ride when it is wet anyway.

I think reliability is a key system component for a commuting rig. While I can fix some of the more common problems, I would far rather not. Hence, my affection for 38mm tires and overbuilt rear wheels (40 spokes with Phil hubs)

I don't carry anything to work. I quit my job.



I carry a ****load of stuff to and from college, it's already a problem I haven't found a good solution to.

I carry a messenger bag where I keep my spare jeans, shirt and socks, spare inner tube and foldable tyre, hand pump, sun glasses and occasionally spare shoes and usually a shed load of shopping.

I used to carry a small pannier for:
1) lunch
2) patch-kit and a mini-pump
3) thin rain-trousers
This does not take much room, so the small pannier was nearly empty most of the time.
Occasionally I stop somewhere on my way home from work and needed space for stuff not related to the commute-to-work.

Now I have recently started to take my 1 year-old to the day-care on my way to work, so I have a carrier for her on the rear rack and no space for the pannier. I have been using a backpack to carry the "luggage" but need to install a a basket or a bag on the handlebar instead (I hate biking with a backpack).

My needs in a commuter:
1) Fully rigid frame. No suspension at all, except for the front and rear air-cushion suspension (a.k.a. tires).
2) Good full fenders, preferably aluminum. Front fender has to be larger than usual in both directions and should have a mudflap.
3) A strong rack.
4) Clearance for 2" wide studded tires. I need these but I realize that this is somewhat unusual demand.

My wants in a commuter. These are things I would like to have but can't afford:
1) Front disc-brake.
2) Internally geared hub. (I think single speed is also a very handy commuter, but I do need gears in the winter time).
3) Generator hub.
4) Good front and rear lights.

I use a Carradice Barley seatbag to carry my commuting gear. In the two side pockets, I carry tools, spare tube and repair kit, spare batteries for my lights and other misc. gear. In the large compartment, I generally carry a clean shirt and t-shirt, underwear, lunch, wallet, cell phone, eye glasses. I could fit more in the Barley, and do once the weather gets colder (eg, arm and leg warmers, vest, gloves), but I try to keep my loads at a minimum.

I keep a lot of spare clothes and supplies in my office so I don't have to carry as much. In my office, I have 2 pairs of pants, a bunch of t-shirts and dress shirts, socks, shoes, shampoo, soap, towels, etc. I also have a small refrigerator, where I keep my lunch as well as a supply of drinks and food like yogurt, cheese. On the days that I drive, I replenish supplies and take home any laundry that has accumulated.

Complete change of clothes, wallet, keys, cellphone and a large lunch in a backpack.

Spare tube, multi tool, snacks, hand sanitizer, pump, windbreaker, vest, safety glasses in a rack trunk.

Lights, blinkies, and water on the bike.

Phased Plasma rifle in the 40 watt range.

check this out!
https://www.youtube.com/watch?v=OzdUw6JBT0U

i like how this fellows bag just click and unclicks from the bike, less stuff for any thieve to steal. A morphing carrier would be really cool (morphing = it shapes up to carry multiple non bicycle related bags example bowling bag, doufle bag, backpack, suitcase, airline carryon laugage...your de designer make it happen =-)

I'm a sheriff's deputy so I carry:

uniform
duty belt (bulky s.o.b.)
weapon
workout clothes (if I'm going to the gym that night)
running shoes (for the gym)
lunch

My boots stay in my locker at work.