People will pay for something they like because they want to ensure its future.

Instapaper does support paywall sites. I have a list of them, that when someone saves something it sends a copy of the page as they are viewing it only to them. If you subscribe to a paid site, you can save the content. I'm not really touching the money.

Charge for something and make more than you spend.

Microsoft loves losing money with online services, so this should stay free forever... unless they get a new CEO who isn't crazy about pouring billions into a hole.

Google won't break into your home. You'll invite them in.

I've worked with many large and small publishers, and nearly all of them love the value that Instapaper provides to their readers.

Instapaper wouldn't be of as much value if it weren't for these mobile and e-reader devices. They give you a separate physical context for reading.