For a limited-time, Citi cardholders can earn an easy 1000 bonus ThankYou® points by linking their ThankYou® and Amazon.com accounts. Simply visit this link and enter bonus registration code TYAMCAZON2. This offer expires June 30, 2013 and is limited to the first 20,000 uses. Your bonus points should post by July 10, 2013.

Note: You can take advantage of this deal even if you already have linked your ThankYou and Amazon accounts by unlinking them first, then entering the code and relinking them. (Via SD)