This stunner of an art-deco bar (cocktails £17) offers gorgeous views, especially of the Thames, South Bank and Trafalgar Sq, from the open-air terrace on the 10th floor of the ME London hotel. It also does food at all hours, including a £30 buffet breakfast, 'brunch' (lunch, really) of burgers, eggs and sandwiches, and all-day dining focused on sharing plates.
Non-guests can't stay in the bar beyond 11pm.