whats the oddest platform layout you've seen?

Try Waverley!

Usually, they are odd because of historical or geographical constraints.

Waverley has 6 (IIRC) through platforms, 4 to the south and 2 to the north side. In the middle is the ticket office / concourse. Two roads go onto the station and form access to the carpark, running in one case along platform 11.

Of the through platforms, three are split in half, with different numbers and scissors Xovers, just to confuse everyone.

There are two bays at the London end of the station, and about six at the Haymarket end. To muddy the water some more, the Scottish side terminal platforms have ticket gates, whilst the English bays don't. Not that they are much good, as you can get onto the Scotch platforms via platform 19.

The combination of gradual development and tacking on new platforms means the numbering is illogical. Platform 19 is next to platform 2, for example.

Keeping it LT, Stamford Brook has a strange platform layout, but that is historical! The former (current eastbound District/Picc roads) LSWR tracks didn't build platforms here, but the District railway built an island platform on their Richmond/Hownslow line. When the Picc was extended to South Harrow its trains used the middle tracks (non stopping) and LT built the (ugly?) concrete eastbound platform for the District Line trains on the former LSWR easbound (Waterloo? via Grove Road/Oylmpia) platform.

What about Borough and White City? Both have right hand running caused by being almost at the [one time] end of the line. At Borough, the tunnels had to roll the wrong way because of the original Greathead tunnels needing to be one above the other to get into King William Street station. At White City, terminating trains used a loop.

Euston city branch southbound platform is an oddity with the remnents of the northbound platform on the southern end. Piccadilly Circus is also strange, with the crossover enabling both platforms to be seen. Southgat is also another oddity where you can see daylight from a tube platform.

I'm interested to see how (if) it turns out!

High Street Kensington is odd because of platform 4.

Kew Gardens is odd.. the only LUL station with a pub on the platform (as far as I know haven't been to them all, or even half of them)..

Woking is odd.. must be one of the longest walks from the ticket gates to a platform (the bay road they have there is miles away)

St pancras is odd.. the only station with a champagne bar on the platforms

Greenford is odd.. the only station in the UK with a wooden escalator

Colchester has the longest platform in the UK at 620m

And I believe uniquely on LU, the escalator goes up from the ticket hall to the platform.

I thought North Greenwich was odd at one time - now I know it's quite normal.

Canary Wharf (DLR) is interesting though.

I believe Greenford is the last one.

From Wikipedia and other sources:

Manchester Victoria and Manchester Exchange - 669m
Colchester - 620m
Gloucester - 602.69m
Pontypridd - 500m (longest in the word when built, it isn't clear whether it is still this length
Cambridge - 470m [given as 514 yards]

The longest in the world (again according to Wikipedia) is Kharagpur, West Bengal (India) - 1,024 - 1,072m (depending on the source)

I've always thought Barking is a bit stupid with all the flyunders and overs to get out the way of the mainline and the bay platform that I always seem to have to change ends in when it's pouring with rain.

I know it's no longer in use but every time I get held on the north curve I try to imagine what the old Aldgate East would have been like, and that strikes me as very strange.

New Cross platforms were not strangely laid out but numbered (or inthis case lettered) A,B,C,D. I always found that a bit weird.

8 car trains used to foul the junctions either side of Aldgate when waiting to enter Aldgate East.

I don't know, but it's probabaly something to do with the Chesham platform because there wont be 4 car S stock.