Yeah, I'm playing with the pricing model. As a side project, I'd like it to at least break even. The NLP required for parsing addresses uses quite a bit of memory, so this increases the monthly costs to keep it online. Also, sending a postcard outside of the US costs substantially more than within the US. I wanted to find a good pricing structure that's flat, regardless of where the postcard is going.

There's room to reduce these costs as more people use the service. As long as I'm breaking even on servers I'll be happy :).