http://www.inat.fr/metro/london/

You might find it easier to save the save it to your hard drive and use
a preview or image viewer there.

Mostly I like it, but some things are deplorable.

The East London line through Whitechapel and the line through Cambridge
Heath are the same colour and almost co-linear, so the eye follows them
as a single line.

Similarly, the Overground lines through Camden Road and South Hampstead
acquire an imaginary Primrose Hill connection if you aren't careful.

The Chiltern line is one of the lowest layers and the Met is one of the
highest layers, causing odd effects where crossing other lines at
Northwick Park and West Hampstead.

The Southeastern services through Crofton Park are missing.

But the portrayal of the West Croydon - Tulse Hill area is an
improvement over the standard LC map... even if three lines of nearly
the same colour crossing over the same spot just south of Selhurst is a
complete disaster.