I remember doing exactly this. An online bookstore had you either call to order or send an email using PGP to order a book with a credit card. Reminds me that

I remember doing exactly this. An online bookstore had you either call to order or send an email using PGP to order a book with a credit card. Reminds me that in 1996-7 we were also usually paying for items by mailing checks on eBay's AuctionWeb.