We went to the London Transport Museum but declined to pay over US$50 for two admissions. My guidebook listed a much lower fee, but the museum replaced that with an annual admission at £15/person. Penny wise and pound foolish, I know, but I couldn't bring myself to pay up.

I didn't know there was a candlelight tour at the Sir John Soanes Museum. I'll be sure to take it on my next visit!