Here's a puzzle for you. All you've got to do is identify the origins of the 26 letters in the graphic above. In most cases these will be precise locations, in others (e.g. the rather easy 'W') a more general case.
A = Abbey Road (the road sign is always covered in Beatles graffiti) B = BBC New Broadcasting House C = Camden Lock bridge D = London Dungeon E = Ben Eine's famous Let's Adore and Endure Each Other message on Great Eastern Street. F = The Fashion and Textile Museum in Bermondsey Street G = A George V postbox (George VI's is more florid) H = Harrods I = Tracey Emin's I Want My Time With You neon writing in St Pancras station J = James Smith & Sons umbrella shop on New Oxford Street K = Brockley railway station sign — one of many painted by Lionel Stanhope L = This is the trickiest one. The letters come from a famous old Lucozade advert that stood for many years on the M4 near Brentfood. The letters are now on show in the Gunnersbury Park Museum, although now in a more complete form than is shown in our photo from 2015. M = Commit No Nuisance signs, found in various locations but particularly the streets just west of Borough High Street. This is another tough one, but regular Londonist readers will know the sign from our Urban Oddities Facebook group. N = One of the neon letters from Ronnie Scott's famous sign in Soho O = The 'O' in Centre Point. We were lucky enough to get a tour of the penthouse recently, and this is the view. P = Mind the Gap. The famous warning comes in many styles. This particular one is from the Lego Store on Leicester Square rather than the tube itself Q = QPR's ground at Loftus Road R = The Ritz hotel S = The Sanyo advert, which held pride of place on Piccadilly Circus for 33 years T = The T of Truman's Brewery chimney, which towers over Brick Lane U = One of the classic tube roundels bearing the word UNDERGROUND V = The Savoy hotel W = Easy one... a Westminster street sign (it happens to be Sherlock Mews, but there's no shame if you didn't get that!) X = OXO Tower, as seen from the inside. We're not sure who the person on the left is Y = BRYMAY ghost sign. Several exist, but this one was near West Brompton station Z = A Zip Oyster — the children's version of an Oyster