'Tir na nog'

At dinner last night amongst other things a few of us were discussing names of places in london and how we shorten them, e.g. Clapham is know by some as 'Clappers', Crappers', and my personal favourite 'Tir na nog' (thanks Tom), no one over the age of 35 lives in Clapham ( have a look next time, you'll be suprised!), it is the land of eternal youth!! There were others, Leicester Square is called Lezzie Square (just easy to say nothing more than that), I call Tottenham Court Road Station Totters and so on. But although I haven't gone through and done this with every single place/station in London, there were a couple that we couldn't get. Brixton and Battersea, so if anyone can help I would be really grateful!