Usually a pencil, #2 of course, or a pen which is found underneath the couch, chair or radiator that is used to mesticulate the carbons of a mixed drink. The mesticulation of the carbons causes fizzation.
You see Danny... The fizzation... The mesticulator... The mesticulation... The carbons.
As for the slang, it's used to define people who are chic/elegant, but not extravagant or yuppie in any aspects. It comes from the term "prep school", or "preparatory school", prolly because people use to assume that members of that kinda school are both educationally and monetarily wealthy. It's also used to define groups, such as clicks and nationalities.
1.Josh: The new dude is such a prep...
John: He must be so fucking rich.
2.Italians, French, Brazilians and Argentinians are like the preppiest people on Earth.
John: Hey look, he's about to do that dare...
Greg: What was he dared to do?
John: He's gonna pull out his sack while he stands on top of the bar.
Greg: The ridiculocity of that situation comes up as 2.1 seconds!!!
(Why 2.1 seconds only? Some people would expect it to be significantly faster, but you have to also increase brain lag when taking into account just how ridiculous something is. If something is just so inconcievably ridiculous, you must understand that some people will not be able to register the information right away.)