This would allow donations to be done using NANO, which is a decentralised cryptocurrency. NANO (https://nano.org/) allows for peer-to-peer transactions to be processed within seconds, requiring zero fees. Also, NANO can process over 1000x more transactions per second than Bitcoin, so you'll never get stuck in a queue.

There are currently multiple payment gateways available, such as Brainblocks (https://brainblocks.io/).