I'd just apply for jobs, with a cover letter explaining that I had reached a point in my career where I could afford to take a sabbatical to focus on personal projects but am now returning to the workforce. If you can show that you didn't completely waste your time and that you've kept your skills up, this break certainly won't help you but shouldn't particularly hurt you either.

Depending on the open source projects you were involved with you may be able to spin that as community service (addressing an industry need that was being neglected), or as exploring whether your idea for a possible productization was worth starting your own company, or something of that sort. You *might* be able to make a plus out of those, if you can explain/defend them well.