I've now finished off the last of my American Express "Offers for You" at Sam's Club, and it was nothing special: I bought a bunch of Sam's Club gift cards, which I'll use to buy cheap stuff (realistically, beer) at Walmart at a hefty discount.
This was my strategy.
Round 1: $20 Sam's Club gift card for $2
When the Offer for You first launched, risk-averse as I am I purchased a $20 Sam's Club gift card to see how they would be coded. I paid $22 (including the 10% non-member surcharge), and a few weeks later when the charge finally cleared, I received a $20 statement credit.
Unfortunately, by that time Sam's Club had implemented two changes: they started charging shipping fees on their own gift cards, and had eliminated $20 gift cards as a purchase option.
They finally relented on the first change, but $50 gift cards currently remain the lowest denomination available for purchase online.
Rounds 2 through 4: $50 Sam's Club gift cards for $15
Fortunately, thanks to Doctor of Credit I knew how to split online Sam's Club purchases between two enrolled American Express cards. So I placed 4 orders for $50 Sam's Club gift cards, putting $20 on one enrolled card and $35 on the other (including the $5 non-member penalty). I received immediate "Congrats!" confirmation e-mails for each of the four orders.
Ultimately, I'll get $200 in Walmart store credit for $60 — a 70% discount on stuff I'm going to buy anyway. My theory is that I spend a lot of time at Walmart already, and they have competitive prices on a few things I purchase regularly. This is the part of our hobby that is closer to extreme couponing than travel hacking, but the price is right.
In many circumstances travel hacking favors the brave: due to my risk-aversion I ended up getting a mere 70% discount on my gift cards, when I could have received a 90% discount if I'd gone all-in while $20 Sam's Club gift cards were still available.
Over the course of a career in this hobby, those differences can add up to tens of thousands of dollars, if not more. On the other hand, sometimes those big, all-in plays backfire: Frequent Miler's scheme to stock up on fruit and nut baskets springs to mind.
Ultimately, I don't have the financial resources to hit every deal as hard as possible the day it launches. So I'll just keep reporting on the slow, steady, and safe methods that make up the bulk of my miles, points, and cash back strategy.