Oyster

The word "oyster" used to bring lip-smacking seafood to mind, but now when I hear the word, this is what I picture:

"Oyster" is the name of the smart card valid on much of London's public transportation, and it's made phrases like "top up," "pay-as-you-go," "touch in," "touch out," and "top out" part of our everyday conversation--exciting, huh? Until December, I was using the supplied oyster sleeve to carry around my card, but when confronted with an amazing array of far cuter sleeves in Seoul (and at about the price of a single bus ride in London), I gave in and shelved my boring blue case for this great one of some sort of strange avian tea party being interrupted by the arrival of a costumed interloper.