A long time ago, I seem to recall reading about anonymous reloadable pre-paid credit cards that you can use if you want to stay off the grid. The idea was that whenever the balance ran low, you could visit your nearest convenience store, hand the cashier some cash and the card, and the cashier would add the cash value to the card on the spot. Did such cards once exist, or am I imagining things?

More generally, are there any anonymous reloadable pre-paid credit cards out there? All of the ones I've found are either not anonymous (you have to submit identifying information to use it) or not reloadable (ex. the one-time Visa gift cards at the store). I see no harm in anonymous reloadable cards since they're still prepaid, and I'm wondering why they're not more widely available.