Amex or Visa giftcards are good, but I think there may be a small fee. I have taken a giftcard as payment 1 time, from a trusted client. I felt confident enough I didn't need to check the balance, and I was right. I requested VS simply because I needed new bras in a different size and at $50 each, it was perfect
Home Depot is good, but not everyone owns thier home so some may not go for that. Walmart has pretty much anything you could ever need, as well as target. If you have kids, cards there are awesome.