Fly a flat bed to Madrid for 25,500 Avios and low fuel surcharges this spring. Economy awards start at 12,750 Avios + $71 or 3,200 Avios and $181 one way.

Iberia is offering a 25% discount on economy and Business Class awards booked by today (2/14/17) between Madrid and:

Miami, New York, Boston, Chicago, Zurich, London, Vienna, Moscow, Bogota, Medellin, Johannesburg, Panama, Shanghai, Mexico City, Lima, Santiago de Chile, Buenos Aires, and Havana

The discounts to/from the USA must be flown by June 14, 2017 with blackouts dates including all of April;

Club Carlson is offering up to 50,000 bonus Gold Points on eligible stays completed through July 31, 2016.

Club Carlson is the loyalty program of these brands.

You earn bonus points for two, five, ten, and fifteen eligible nights:

Eligible nights are basically paid nights.

Updated 1/27/16 because the offer ends tomorrow.

United has announced a 20% to 25% discount on economy class awards from the United States to Sydney, Australia:

Roundtrip awards booked between now and January 28, 2016
for flights flown between February 2 and June 22, 2016
on itineraries wholly operated by United and United Express flights
will cost only 60k to 64k miles roundtrip, depending on the days of travel

United has run nearly identical promotions for travel to Europe and South America for the last several years.
United’s Current Promotion

I did a few dummy bookings to test out what’s

Delta is offering awards to London for 22,500 SkyMiles each way this winter. That is a 7,500 miles discount off the normal price.

The details are a little sketchy (just like Delta's lack of an award chart) because those listed on the promo page are incomplete and incorrect:
Origins & Destinations | Round-trip Award ticket and sale fares for travel from select U.S.

Through February 15, IHG is running a promotion that offers a prize for every stay beyond your first. Since the prize is randomly drawn, though, IHG had to offer a free way to enter to avoid violating lottery laws.

All you have to do is send a hand-written note to IHG's prize fulfillment company, and you get an entry. You can get 94 entries this way.

Read the comments (at least the most recent ones) for updates. People are receiving their game plays and notifications of their prizes, though the actual points haven't posted.

IHG and MasterCard have announced a Priceless Surprises promotion that allows you to win 47,000+ IHG points from home for $56 and a few hours of your time.

The way the promotion is supposed to work is that you get 1,000 points for your first qualifying IHG stay with a check in date between November 15, 2015 and February 15, 2016.

IHG has comes out with its Fall Promo, Accelerate, for stays between September 1 and December 31. Registration is required to see your targeted offer. I don't stay in hotels much, so hotel promotions only catch my eye--and make an appearance on MileValue--when you can earn rewards worth more than the price of the hotel rooms you need to book to earn the rewards.

Starwood Preferred Guest has two summer promotions that should be stackable, and for some people, the value of the promotions will make mattress running a viable option.

The first promotion--Make It Count--offers 1,000 bonus Starpoints for each eligible 2+ night stay that includes at least one weekend night. Eligible stays must be completed by August 31, 2015.