In 2002 the investors behind Blender launched the "Free Blender" campaign. They asked for 100,000 EUR as a one-time fee for open sourcing it. At the time the project was dying as a proprietary product. The investors got the money and today Blender is a healthy open source project.
I would love to see something similar with Sublime Text. The author seems uninterested in continuing with its development while many users want to see it moving forward. I believe it can raise much more money than Blender at the time.