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.

Can you use one oyster card for multiple people/journeys? or does each person require their own?

Once I have swiped it, I just pass mine back to whoever i am with... it doesnt matter, as long as there is credit on it... This is from TFL Website :

"You can give your Oyster card to someone else"

If your Oyster only has pay as you go credit at adult rate on it you can let someone else use it, even if the card is registered in your name.

I bought a zone 1-4 travel card, lets me use the bus and train as many times as I want for £8. It depends where you plan to go etc but if you plan to go back to the hotel then out again to another part of London as we do, then the travel card works out cheaper.

agreed, oyster is the way forward, why on earth all bus and train companies dont use this system is beyond me...would be a uk travel card then, accepted on any form of transport,werever you are......
black cabs should also accept them, that would be even easier

each person needs an oyster card..... you cannot get more than one person through a gate with one card... unless your with your kids, inwhich i think 4 travel free with a paying adult (age limit)......
oyster card is a pre paid, top up card which is used on all transport for london journeys inclding DLR......
swipe your card over the yellow oyster logo at the gate, and then when you alight your destination tube station make sure to do the same on the exit gate, this will automatically deduct the cheapest fair possible from your credit balance...simple as........
i top mine up with £20, and that does me for a full weekend in the capital.... and that includes trips to twickkers for the broncos game!!!

Another tip for those new to Oyster:

When you swipe in at the start of your journey make sure you swipe out even if the exit gates at the destination station are open. If you don't then it will appear as an unresolved journey and you'll be charged the maximum fare that you could have incurred on the network - £8.30 (when you swipe in it deducts £8.30 from your balance, when you swipe out it credits the difference in fares back to your card - don't swipe out = no credit)

Yeah Oyster is the best option.. and don't bother waiting in line to get your deposit back in the end.. just keep it for next time.

Just bought 3 Oyster cards from the TFL website.

Delivery in 2-4 days.

Saves queueing to buy tickets and will come in useful for future trips.

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

I like your optimism!