There aren't too many restaurants around that let you eat in a treehouse while looking down at a warbling opera singer. It can get hot and stuffy up high when it's busy, but this little place just ten minutes walk from Clapham Junction is worth the trek. It's so cheap you'll wonder whether they've made a mistake - could mussels in white wine really cost less than a fiver? The atmosphere's a feast in itself. Book ahead if you want a good spot at the normal time.