Here's my beast, a Worksman Cycles Super Utility Delivery trike, with the customary heavy metal box replaced by a shopping cart. I've been commuting four miles each way on this for about a month, since my other three bikes are all in various states of getting repaired.
Of course, I don't usually cart another adult all the way to work, but I do use it to drop off my six-year-old at school, and I frequently stop for major grocery buys on the way home. It's not a fast ride, obviously, but it only adds between five and eight minutes to my commute (from 20 minutes to nearly half an hour), and I get the benefit of having every hill turned into a serious cardio workout. (It also makes carrying my suits from the dry cleaner's to the office a lot easier.)
The people in my office make (good-natured) fun of me, naturally - today, someone called it "a highly modified geriatric tricycle" - but I tell myself they're just jealous. After all, I get favorable comments practically every day during my ride through the ghetto. Recent pedestrian remarks have included, "ˇEsa sí es una bicicleta, brother!" and "Yo, that sh*t is NICE!"