Eccentric and surprising house and museum of architect Sir John Soane. Mostly unchanged since his death over 180 years ago, it is full of atmosphere. Also have spotlit, late night openings.  

Great little independent bookshop in central London run by Tamsin Clark. Weird and wonderful selection of photo books, magazines, artist books, poetry and more.

A charming family-run restaurant offering a great selection of freshly made hand-rolled pasta. Delicious:p

A beautiful, neon-fronted, old school, single-screen cinema on Upper St. That anyone would choose to go to the Vue just up the road is baffling

Just above the Dorfman Theatre lobby at the National Theatre, is the entrance to the high-level walkway, a public walkway that overlooks the National Theatre props and scenic workshop. It's free and is a unique chance to get a glimpse of what happens backstage. I love popping in when I'm on the south bank, as you get a completely different sight each time, depending on which production the workshops are working on at the time.