Most recently, I transported a unicycle. Me and my housemates decided to take advantage of the sunshine and ride to the local park, and one of them wanted to bring his unicycle. It's a surprisingly awkward thing to load onto a bike. After a couple of false starts with the idea of towing the thing, we eventually managed to secure it to my rear cargo rack with a couple of bungees and a bike lock, with the saddle pointing out behind the bike. It certainly drew a few odd looks from people driving past.