The Limehouse Golem - Danny. 6' 6", red hair, corpulent, on some heavy meds for various psychotic episodes. Every so often he'd stop taking them, and cycle round Limehouse, Poplar and Bethnal Green yelling abuse at car drivers. If he found an abandoned cone beside the road, he'd get off his bike, set the cone up in the middle of the road and start directing traffic around it. He had taken the whole cycling radical thing too much to heart.
Then there's the wierd courier in the City of London. Late 40s, no teeth, skinny, dressed like a tramp, CDs, teddy bears, basket on his bike, radio taped to the handlebars, bags and bits of string hanging off him and his bike. Basically looks likes he's homeless, but is holding down a job as a courier.