We are obviously celebrating Saturn here (Cronos to the Greeks, although they are exact pairings in my opinion) and during this week everything goes. If it is fun, do it. Like to eat? Feast while shouting "Io, Saturnalia!" Like to gamble? Throw your dice with wild abandon. Like to sing naked? You're in luck.
What is pretty cool about this celebration is the fact that slaves participate. In fact, this seems to be more of a slave's holiday than free man's. During the holiday slaves don't work, they can dress in their master's clothes, they can be waited upon at dinner, and they get to wear these nifty little felt hats called a pileus.
Social lines are broken down and you can associated with anyone as equals during these days. You have a mean boss? Well, hang out with him and take him to a local chicken wings restaurant. Challenge him to a trivia game at a bar. Whoever wins can get a laurel. Sure, things will go back to normal next week, but for now, live it up. Or you can just do like Pliny the Younger and hide in your bedroom until it is all over.
So what are you waiting for? Decorate your house with festive greenery! Give some gifts! Break some laws! Io, Saturnalia!
Most of this information I got from the latin teacher down the hall, this website: http://www.squidoo.com/saturnalia, and this website: http://penelope.uchicago.edu/~grout/encyclopaedia_romana/calendar/saturnalia.html. Picture from: http://www.alanbaxteronline.com/wp-content/uploads/2008/12/saturnalia-1.jpg