I've used ThankYou points to top off my award balances in programs like Singapore Airlines and Flying Blue.
Brad's Deals Editor Mark,
Earn 50,000 bonus ThankYou® Points after you spend $4,000 in purchases within the first 3 months of account opening with the Citi® ThankYou Premier card. You'll also earn 3X points on travel, including gas stations, 2X points on dining out and entertainment, and 1X points on all other purchases. Points are redeemable for $625 in airfare on any airline, anytime with no blackout dates when booked through the ThankYou® Travel Center, or $500 in gift cards when redeemed at thankyou.com. There are also points transfers, that allows you to transfer points to participating airline loyalty programs. There's no expiration and no limit to the amount of points you can earn with this card. There are no foreign transaction fees on purchases. The annual fee is $95, waived for the first 12 months of membership.