dooflotcher
Any miscellaneous or random item, especially one whose name escapes you at a particular moment. Analagous to thingamajig or doohickey.
Individual A: Hey, where's my dooflotcher?
Individual B: You mean your keys? They're over here.
Individual A: Thanks, man.
Individual B: You mean your keys? They're over here.
Individual A: Thanks, man.