So, I was just wondering what other cross-platform interchanges there
are on the underground.

I'm thinking of things like Victoria line and Northern line (Bank
branch) at Euston, Victoria line and Bakerloo line at Oxford Circus,
Victoria line and Northern City Line at Highbury & Islington.

I'm curious as to what others there are?

roy

Barons Court, Hammersmith, Turnham Green (at certain times) and Acton
Town Piccadilly/District
Mile End District/Central
Stratford UK Rail/Central
Finchley Rd and Wembley Park Metropolitan and Jubilee
Baker St Jubilee/Bakerloo
Edgware Rd Hammersmith and City/Circle if you're lucky

Highbury & Islington: Victoria - Northern City Line?
--
Robin
reply to address is (meant to be) valid