Oyster cards are the way... Order online and its a one off payment of £5 for card & registration etc... you just log in and top it up with a credit/debit card. I have put £25 on mine this time, as we are there for 3 days, so will deffo cover us from hotel to Wembley, back to hotel and to Camden Town on the night etc and into central London... Oyster can also be used on buses that are 24 hours in London.. so it`s a no brainer for me... especially with the costs of taxis down there.

Nope, sorry, you've misunderstood that rule. It doesn't mean at the same time.

If you got stopped by a ticket inspector you would only have one valid ticket for two people and could cop a fine.

Not at the same time, no.

You can lend an Oyster card to somebody when you are not using it as per the rule Biff posted.

All this talk about Oysters is making me hornyyyyy

Yes, very good tip and make sure it beeps when you do swipe it. I got an unresolved charged a couple of weeks ago even though I thought I had tapped out. Although to be fair, they did refund it when I challenged it.

I like your optimism!