International
https://stripe.com/
Payment Options
Tax & Vat Compliance
http://developer.avalara.com/api-docs/designing-your-integration/testing-your-integration-to-avatax/vat-transactions
https://www.postmen.com/
http://dev.taxcloud.net/2013/10/03/taxcloud-js_stripe/
http://www.avalara.com/avalara-avatax-with-global-calculation/
Logistics
http://www.shipwire.com/why-shipwire/