If this room is rockin', don't bother knockin'. That goes for cages and sockin' too. Unfortunately, not everyone gets the message. Sock it to those wonderful if out-of-it bird lovers on your birthday list if they've grown too old to remember those early lectures about the birds and the bees. The hilarious Sock on the Doorknob Birthday Humor Paper Card from NobleWorks Cards will give them a graphic refresher course that will knock their socks off.