Stripe is intimidatingly good. A test mode that you don't need to sign up to play with. Excellent sinatra sample code for webhooks. Then, I read their backgro

Stripe is intimidatingly good. A test mode that you don't need to sign up to play with. Excellent sinatra sample code for webhooks. Then, I read their background, which is also intimidatingly good: funded by PayPal founders; one co-founder was a YCer with a $5 million exit at 19yo. (http://news.ycombinator.com/item?id=3539414 http://news.ycombinator.com/item?id=3539414) I have one suggestion: for the browser test mode, allow invalid CC numbers (or, provide a test CC number), so one doesn't have to go and find and type in a real-life credit card, to try it out.