What do you want to do at the small disruptive B2C software company? Are you wanting a technical development position? Product Management? Operations management? Partnership development?

It occurs to me that being "incredibly well compensated" at your current position could be both at the heart of the problem as well as holding the solution.

Problem: If you are already making 2X or 3X of what the small disruptive company is paying anyone in the company today it is really hard for a founder to figure out where to slot you in, and to believe that you will stick around and stay motivated for 1/3 your current salary.

Solution: If your compensation has been well managed then you should be in a position to invest several hundred thousand dollars. And that, combined with your sales and management experience might be really attractive to a technically sophisticated founder who needs a co-founder with business experience.