Here's a great promo from Uber and American Express. You get $25 any one ride with Uber's UberBLACK service (nicer cars than UberX) when paying with your American Express card. The promotion is valid until January 31st and only in New York City, which includes Brooklyn, Bronx, Manhattan, Queens and Staten Island.
To apply the promo code, open the Uber app then go to PAYMENT, then Add Promo / Gift Code and enter in AMEXBLACK. Here are the full terms and conditions:
Terms and Conditions
To redeem offer, you must apply the promo code AMEXBLACK in the promotions tab of your Uber app prior to requesting the UberBLACK ride. Rides must originate and end in one of the five NYC boroughs: Brooklyn, Queens, Manhattan, Staten Island and the Bronx. In the "Payment" section of the Uber App, you must select an American Express® Credit or Charge Card as the payment method when requesting your ride; Prepaid Cards not eligible for offer. The discount will not apply to previously taken Uber rides or rides paid for with a digital wallet. New and existing Uber users are eligible. Uber will apply discount of up to $25 at the point of sale. Limit 1 discounted UberBLACK ride total per Uber account. If the cost of a ride is less than $25, you will only receive a discount of the cost of a ride and you will not receive the difference between the cost of a ride and $25. If the cost of a ride is more than $25, the remaining balance of the cost will be charged to your Card. The discounted cost of a ride will be displayed on your post-ride email receipt. Fulfillment of this offer is the sole responsibility of Uber. Offer may not be combined with any other offers. If ride is eligible for another promotion that you have added to your Uber account, only the most recently added promotion will be applied to the ride. Enrollment limited. Must complete rides by 1/31/17.