Amazon is currently offering the 32GB Nexus 6 for just $199. The 64GB model has been discounted to $259. The deal is valid only for today, and is applicable on both the Cloud White and Midnight Blue color options.
No idea how long the retailer's stock will last at these prices, so be sure to get your order in if you've been holding out on the phone.
Thanks jordangriesshaber and Boris!