The Electric is an amazing little theater on Portobello Road. Although it is tied in with a member's club, it is also open to the public and is surprisingly competitive with the Odeons and other mainstream cinemas of London in terms of cost despite offering considerably posher viewing conditions.
The theater has somewhere around 100 seats, ranging from ordinary cinema style seats up front, to more casual loungers with footrests in the back rows and even a pair of somewhat scandalous seeming 'couches' (they look more like beds to my eyes) tucked away in the back for couples to cuddle on in the dark room. The screen and sound quality are top notch, and there is also a full bar with a range of fancy snacks to nibble on during the film.
The range of films tend to be somewhat eclectic, and online reservation for tickets is almost essential, as the seating is limited and usually all reserved well in advance of the screening. Still, considering how outrageously priced the regular cinema is, from tickets to concessions, I don't see any reason to ignore a more comfortable and swanky option like the Electric.