My commute is 23 miles round trip. I carry a full change of clothes in one of my front panniers. In the other pannier are a change of shoes, lunch, wallet, cell phone, etc. We have shower facilities at work, so I leave soap/shampoo there.

My commuter has a rear rack and front low-riders. I run full fenders, and have an assortment of lights (dyno- and battery-powered). I carry a spare tube, patch kit, mini-tool, and pump. Tires are Vittoria Randonneur Hypers which have protective shielding.

Without bags, my bike tips the scales at ~32 pounds. I chose everything with a nod towards reliability, however. It gets me to/from work rain or shine, day or night.