Inspiring! A question: How much did it cost (in dollars, not sweat) to get these services started, and how much is it monthly?

I'm surely off-base, but I feel like it "should" all be free for something getting started (ie with very little traffic), because it would be a great way for all these services to get many initial users, some of which will become paying.

EDIT answers:

Heroku: free for dev, $15/month for production (it seems?) http://heroku.com/pricing#blossom-1-0

Sendgrid: free for 200 emails/day http://sendgrid.com/pricing.html

Charify: free for 50 customers http://chargify.com/pricing-and-signup/