In message , at 09:31:38 on Thu,
26 Aug 2010, Ian Jelf remarked:

Can you just take a PAYG-loaded Oyster Card to a Ticket Office and cash
it in for a refund of the balance (and deposit if applicable)?

Doesn't it have to be registered, and the money paid to a bank account
later? Won't there be a bit of a long queue at Heathrow tube station (or
wherever is the OP's point of final exit from the "TFL system".
--
Roland Perry