Last time I was in London, we purchased those REALLY expensive 5 day passes (I think it was 5 days), and it was well over 60 pounds if I recall, for two.
this time I just want to purchase an oyster card and pay as I go...we will be there for another 5 time stretch, so I feel it'll be worth it...and we plan on going back again anyway...so we can use it again, and again.
So, as an American, I know I cannot register on the oyster site, but is there anyway to get cheap oyster cards?