Sport Mart, boxing day last year. Mad_Trix, $130.
Preparation - Do some reconnaissance the day/night before, know exactly where the stuff you are buying is. Sketch the layout of the store, and plan your attack route.
The Big Day - Put Red Bull in your cheerios instead of milk. Wear spandex or something else tight so you can weave through the crowds. Cover yourself with vegetable oil if you want to be real slick. Ninja gear is stealthy, but not meant for snaking through crowds, so don't even try.
The sale - Get there early! Follow your plan. If you get in an argument over who grabbed a ski or hat first with another customer, mark your territory by urinating on it. Once you have your stuff, proceed to the cash register, and get out of there as fast as possible. Bring the goods back home, and go back for more! There might be new stock on the shelves... or you can try to buy the shelves.