Right now all Kroger stores are participating in an instant win game, called March to Savings - Free Shot Challenge. Just head over to the Kroger site, select your local brand of stores and them click to play them game. There are over 50,000 prizes. To see all the items you could win, click here. You can play the game daily through March 24th. So lots of time to earn lots of prizes.
I played and one on my first try... beginner's luck I guess :)
ALL prizes expire on April 11, 2012. Load and redeem your prizes in store before then.