The folks at Thoughtbot recently announced a pricing structure for their Hoptoad app, and they’ve included a special treat for users who signed up before the app cost anything.

I’d like you to go carbon-neutral for a day: on me.

When I decided to start work on Matchbook, my online appointment software service, I didn’t know how much it would cost to develop and launch, and although I haven’t launched it yet, I think the total cost will be very low indeed.