The phenomenon of smelly pee is well known as relates to the consumption of asparagus. But the other day, I noticed I was producing some strong-smelling stuff and hadn't had any asparagus. The night before, however, I had some delicious stir-fry that heavily featured the chinese cabbage known as bok choy.
As a member of the cruciferous or brassicaceae family of vegetables, it is kin to asparagus, broccoli, Brussels sprouts, cauliflower and others that have the ability to by-produce odoriferous urine. It was strong, pungent, and distinctly different than asparagus pee, but bok choy was the culprit. It wore off after about a day.
There's not much authoritative stuff out there on the Interwebs on this topic, so I thought I'd weigh in just in case you haven't eaten asparagus and are producing smelly pee. If you haven't eaten bok choy either, one other culprit is sexually-transmitted disease (STD), in which case you should probably get your junk checked out by someone who went to medical school.