Sony doesn't usually compete on price in the e-reader space, but the company's making an exception this year -- until December 24th, you can pick up a Sony Reader Wi-Fi for just $99. The Android-based touchscreen e-reader originally cost $149, and got a price drop to $129.99 just days ago. At $99, it's finally going head to head with the Kindle Touch and Nook Simple Touch this Christmas. What makes it a true deal, though, is the trade-in program Sony's offering right now. Give Sony any old e-reader, and you can take another $50 off the price. That's $49 for a handheld e-ink device with Android hacking potential. Now we're talking.