B&N is back with a B1G1 free on selected titles from the Criterion Collection starting Tuesday 12/10 and going through Monday 12/16 online and in store. I'll post a link to the sale when it shows up on the B&N site.
From the sale description:
Buy one (1) qualifying DVD or Blu-ray from our Buy One Criterion Collection DVD or Blu-ray, Get One Free promotion and get a second Criterion Collection, DVD or Blu-ray of equal or lesser value free! Simply look for the Buy One Criterion Collection DVD or Blu-ray product page icon or message or store product label on select DVDs and Blu-rays. Limit of ten (10) redemptions per customer.
via DVD Talk
Edit: Link to B&N page.