It was thought that absinthe enhanced creativity, and from the middle of the 19th century to the early 20th, the anise-flavored concoction was available in cafes; barkeepers would bring patrons a new saucer with each drink, and used the number of saucers that were stacked to tally how much to charge.
By the early 20th century, however, absinthe had gained a very bad (though undeserved) reputation as being mind-altering and responsible for immoral/bat-shit crazy behavior. It was banned in both Europe and the U.S.
Absinthe is no longer illegal as of 2007, and it has apparently been making a comeback.
There is a ritual associated with the beverage: absinthe is served in short glasses, often with a bulb at the bottom or some other indicator of how much absinthe to add to the glass. Pure absinthe is usually clear green in color (hence its nickname), and extremely high in alcohol content; a small, decorative slotted spoon is laid across the top of the glass, and a sugar cube is placed onto it. Ice-cold water is then poured over the sugar and spoon. As the sugar and water are filtered into the glass, the liquid becomes cloudy and beautifully pearlescent. Then you stir and enjoy.
Victorian Trading Company-- a deliciously gorgeous site on which to browse and fantasize-- actually sells absinthe goblets, spoons, and decanters. And there is a 1920's-themed restaurant in my city's downtown that serves absinthe; I figure that it would probably be a good idea to actually try the stuff before I decide to get goblets and spoons (forget the decanters, which are waaaay out of my price range). I love anise, which is the predominant flavor, so I doubt that I would dislike it.