If I were Mozilla, I'd focus my efforts on creating a search engine. Search engine tech and computational resources are available these days and dare I say it's perfectly feasible to create an alternative to Google. In addition to that, create a Google docs or at least good Gmail competitor. They have the technical talent to do it, and they could capture a real market of people who would pay for such products, if done well, that are concerned with privacy and don't want to use Microsoft or Google products.