My Bikes At Work trailer http://bikesatwork.com/

Works great. Cool website too. You can calculate how fast you can expect to pull a certain weight over a chosen grade.

This trailer really allows me to be car free more easily. It will haul over 300lbs of stuff. Rubber tubs not included. I think I paid $400+ US a couple years ago and saved that in car note over a couple months. Very well made and nice design. Pulls like a charm. I would suggest a triple chain ring tho.