Yesterday (Sunday) I needed, for complicated reasons, a ticket that would let me travel from Cambridge to Finsbury Park (on FCC) and ideally return from Tottenham Hale (NXEA)- I'd usually travel just on the West Anglia line (cheaper, gets me where I actually need to get to) but that was shut in the morning with a coach service from Stansted 
Now, normally you'd expect this sort of Open Leg return to be, under UK ticketing, impossible. But a bit of sleuthing on the part of the ticket seller at Cambridge turned up a destination of:
"Zones 2,3,4
Victoria Line Nth"
Which, as both stations are covered by that description, was exactly what I needed. £12.55 with a railcard didn't seem too bad either.
Somewhat confused as to why it isn't just "Zones 2 & 3", what with Walthastow Central, the terminus, being in 3 (with Brixton, at the south end, being in 2).
Now, normally you'd expect this sort of Open Leg return to be, under UK ticketing, impossible. But a bit of sleuthing on the part of the ticket seller at Cambridge turned up a destination of:
"Zones 2,3,4
Victoria Line Nth"
Which, as both stations are covered by that description, was exactly what I needed. £12.55 with a railcard didn't seem too bad either.
Somewhat confused as to why it isn't just "Zones 2 & 3", what with Walthastow Central, the terminus, being in 3 (with Brixton, at the south end, being in 2).