From 23andMe: "To show our appreciation and to encourage others to join in this research revolution we are giving you a $50 coupon that you can share with as many people as you like. This coupon expires in 7 days (August 9, 2011) so make sure you get the word out fast." At current prices that works to 24% off for the yearly price ($9/month X 12 months + $99).
(this is for "new customers only")