Ancestry.com offers its Ancestry.com AncestryDNA Kit for $99. Coupon code "FREESHIPDNA" bags free shipping. (You'll need to register for a free account.) Although it was $20 less two weeks ago, that's still a savings of $10. Features include a breakdown of your genetic ethnicity, relatives matches in real time, integration with your Ancestry tree, and automatic updates.
Update: Use this link, to drop the price to $89 plus free shipping via the coupon code above.