First, let me say that while this practice is not advised, it does occur frequently in my own dorm-room, and not infrequently in many I have visited. The use of a screwdriver as an ashtray is a behavior which springs from four circumstances, all of which are common in the average dorm room.

ONE: A person is smoking.

TWO: That person is highly inebriated.

THREE: That person has a screwdriver which he/she no longer cares to imbibe (this can be due to any number of reasons, including a poor mix, the spins, complete drunken apathy, or another person using the screwdriver as an ashtray just to be a fucker).

FOUR: The actual ashtray is all the way across the room.

The interesting part about using a screwdriver as an ashtray is that once this process has begun, it becomes more and more fascinating to continue using it as such. This is because the screwdriver itself will seperate, forming two layers, one being an opaque orange layer, consisting mostly of orange pulp, and the other being a clear layer, consisting of alcohol and water. When burned cigarettes are dropped into this mixture, the filters will float on the top of the water/alcohol layer, while the dead ashes will settle into a hover between the two liquid layers. because the filters will actually soak up only a small amount of the liquid, the addition of more butts will affect the layers very little, while the loose ash will continue to build up between the liquid layers. since the layers will not form evenly all the way around, nifty little patterns, much like the layers in a glass bottle filled with multi-colored sand, will form. After several days, the clear layer will begin to turn brown, but will stay transluscent. This process may be continued ad infinitum, until someone gets sick looking at it, or the wet butts begin to grow mold (this will occur about a week after the OJ has been left out).