From The Consumerist:
Free Grand Slammwiches At Denny's April 8th
If you bring a friend with you to Denny's April 8 between 6am and 2pm and order a Grand Slam, your friend will get a free Grand Slamwich. Not quite the same as their totally free breakfast promo after the Superbowl, but there's still free food involved. Besides, going to Denny's by yourself is a little depressing.