In the words of O.A.R. (that kind of apply), "Who's up for Game 3?!"
NOTE: Some of these are recent discoveries, while others are words that I have actually incorporated into my vocabulary and have only realized in a recent spree of postcard writing and Skype chatting are not quite "American." (Sorry for the awkward grammar in that last sentence, by the way...)
bollocked - reprimanded, e.g. "He just got bollocked for coming in so late."
fag - smoke
lift - elevator
chips - French fries
crisps - potato chips
pence - equivalent to our "cents"
courgette - zucchini
rocket - arugula
Slightly Different Usage
stroke - "slash," e.g. "and/or" might be said, "and stroke or"
mate - friend
-monger - someone dedicated to something, i.e. "cheesemonger," "salesmonger," etc.
chap - guy
aubergine - eggplant
bonkers - crazy