Tube shoes!

Check out Above and Below London's Recycled Shoes - made from old underground train or railway seats (and also, old rubber tyres!) How absolutely cool!
There's various prints from various lines:

Favourites:

Central

Bakerloo

District Line #1

District Line #2

Naturally, out of principle, I'd have to have the first District line one, which is of course famously featured in this painting:

But actually, I think I like the Central line one best. The colours are nicest.