Amazon offers Prime members The Departed on Blu-ray for $5.99 with free shipping. (Best Buy charges the same with free store pickup. Non-members can spend $35 to bag free shipping; otherwise, it adds $4.98.) That's the lowest price we could find by $2.

Update: The price has increased at Amazon; however, Best Buy still offers it for $5.99. Choose in-store pickup to avoid the $3.99 shipping charge.