Maths. Yeah it's a while but I was having fun; at the end of each 2-3 year contract someone would say "would you be interested ..." and I'd take it up. While my work was pretty solid, it wasn't stellar and I didn't really publish enough to warrant a lecturer post, I realised that early on. I once met a woman who'd been doing non-standard analysis (which is both left-field and old-school) as a postdoc for years and I asked her if she saw a future in it, "not really, but while the music plays, I will dance".