Some might know this already, but I just came across this and thought I'd share:
Mobil 1 rewards program:
http://www.mobiloil.com/USA-English/MotorOil/Rewards/Mobil_1_Rewards.aspx
Seems that for every case (six quarts) of M1 you purchase, they send you $5 towards either "Mobil 1 Merchandise" (mostly boring stuff), or (more interestingly) you can use it at http://www.giftcertificates.com (movie tickets, Sharper Image, etc) . Limit of 24 cases per 12 months.
Mobil 1 rewards program:
http://www.mobiloil.com/USA-English/MotorOil/Rewards/Mobil_1_Rewards.aspx
Seems that for every case (six quarts) of M1 you purchase, they send you $5 towards either "Mobil 1 Merchandise" (mostly boring stuff), or (more interestingly) you can use it at http://www.giftcertificates.com (movie tickets, Sharper Image, etc) . Limit of 24 cases per 12 months.