Oh, man, the Hyatt FFN and the US Airways Grand Slams are bringing back some memories. US Airways had some really nice redemption sweet spots too. 55k R/T Envory off-peak to Europe. 80k R/T J on partner carriers to a liberally-defined North Asia region. Plus SWUs that were pretty easy to use on paid fares and awarded at mid-tier, whereas most airlines require you to hit top-tier to get SWUs.

Other honorable mentions: SPG often had promos that rivaled the Hyatt FFN. AA used to have good anniversary promos (using partners like the US Grand Slam). Hertz had a weird one where every couple of rentals you'd get a free piece of luggage. One-off thing they did with Samsonite, I think. I still have a couple of the bags in my basement somewhere. The old Hilton Conquest bonuses, circa 2001. (Those were incredibly lucrative, before much of the world had figured out hotel programs. You could turn a few Hampton Inn nights in to 6 free nights in Hawaii at their top resorts.)

Marriott always lagged in promos, but made up for it with their Elite Exclusive Offers booklets, which always had Marriott and Renaissance weekend BOGOs and a variety of other really good deals.

Modern times? Not much out there left. I occasionally run into little extras like the Hyatt free night for using 5 brands, but nothing that I chase the way we did when Milesbuzz was THE place to be on Flyertalk for all of these kinds of deals.