There is a current American Express Offers for you that gives a $20 statement credit for spending $20 at Sam's Club.
For a couple of days people were buying $40 gift cards until they disappeared and then Sam's Club added a large shipping fee to the $50 denominations, making them far less lucrative to buy.
Well, $50 Sam's Club gift cards are back
Keep in mind that Sam's Club gift cards can be used at Walmart as well, though they can be a pain to activate. If nothing else, you should be able to sell them to SaveYa for 90.8% as Walmart gift cards.
If you use 2 American Express cards per transaction, you will save $40 off the price. It will be $10 for the $50 of gift cards. The gift cards can be sold for $45.40. That's a whopping profit of $35.40 for every $50 gift card you buy! Not too shabby!
$10 gift cards available in the same link but there is a minimum of 10 per transaction so that isn't useful.
Sam's Club Membership
The last groupon deal was for $45 for a Plus membership with a $20 gift card. You can wait for it to see if it comes before the offer is over!
If you are buying a membership, go to Top Cashback first and you can earn 7% cashback on your membership. You won't earn anything for the gift card purchase, but at least you will earn for the membership.
Refer a Friend
Sam's club apparently has a refer a friend program as well.
Refer a Friend a receive a $10 Sam's Club eGift Card