- Brain Tree Payments
- Coin Base
- Coin Payments
- Dwolla
- PayPal
- Payza not available to people in the U.S.
- Skrill
- Solid Trust Pay aka STP
- Stripe
- Transfer Wise
- Uphold
- We Pay
Some Payment Processor sites have fees and other requirements. Some are very hard to sign up for in the first place so after you get your sign-up done, you should really use the service(s) that the site offers.