Enveloupe - Send snail mail in three clicks.
MyBrocard - Brocard allows you to create an unlimited number of virtual cards for paying for advertising and other online payments, manage a team of buyers, choose from 20+ bins for various tasks, and enjoy convenient API for integrations.
Felt for iPhone - Handwritten cards for the modern world
Coinramp - The Coinramp Card lets you spend over 10+ cryptocurrencies like cash, online, in-stores and ATM withdrawals. Available in 100+ countries, no ID needed. Anonymous Crypto Cards
Skip The Stamps - Snap or upload a pic to send a physical postcard in minutes
PST.NET - Virtual payment cards for online shopping and advertising