Barnes & Noble is running a Mother's Day deal now through May 12th that knocks $20 off both the Nook Simple Touch e-reader and the Nook Color tablet. Of course, you don't have to prove that the purchase is for your mother, so that means that anyone can take advantage of the offer. The discount brings the Nook Simple Touch down to $79 (a 20 percent discount), and the Nook Color only costs $149 with the deal (an 11 percent discount on top of its recently reduced $169 price point). While both of the devices are current models, they're not the newest offered by the bookseller — the Nook Tablet with a faster processor and the nighttime-friendly Nook Simple Touch with Glowlight take those honors. If you're interested, you'll be glad to hear that there's free shipping, but the deal's valid in-store, too.