Eat Paczki.
It ain't called Fat Tuesday for nothin'. These fried, jelly-filled pastries are traditionally made by Polish people to get rid of the forbidden sugar, large, eggs and fruit in their homes before Lent. Whether or not you're Polish (or religious), you should pick up a few of these decadent treats at one of many bakeries or grocery stores around the city. Centerstage offers a great list of paczki purveyors.

Drink Hurricanes.
There's no better excuse (ok, maybe St. Patrick's Day) to get a little tipsy than the all-out celebration that is Mardi Gras. Not surprisingly, Chicago bars and restaurants are taking full advantage of the day, with bead- and mask-filled bashes galore. Find a Mardi Gras party in your 'hood.

Laissez Les Bon Temps Rouler!
It's not a true N'awlins celebration without some good music, and Chicago offers plenty of that today, with special performances including Houseman & the Housewreckers (Martyrs'), Paul Cebar and the Modern Sounds (FitzGerald's) and the king of all parties, Snoop Dogg (Metro). Leave your inhibitions at home.