[sahillavingia]

Instapaper is the (or at least, my) defacto example - http://instapaper.com/

Two of my iPhone apps, Color Stream and Dayta have turned into profitable businesses, even though they were just pet projects (and still are).

[_b8r0]

I love Instapaper and bought the Pro version for the iPhone the minute it came out as I wanted to give back. Just introduced my wife to it too (as I thought it might be too much hard work for her to learn yet another toy of mine), she loves it!

[bignoggins]

Awesome, I had no idea Dayta and Instapaper were the same developer.

[rbarooah]

They aren't.

[jcromartie]

I use Instapaper on the iPad every day.