You can always choose some qualitative attribute or perk about your job, just like businesses use, and put a monetary value on that to you. The value becomes subjective and you can use that as a reference if you decide you do want to disclose or inflate your salary to negotiate higher for a new position. This is more difficult if the person happens to be familiar with a given businesses rates but businesses are often so secretive about comp rates (for their own advantage) that even management within companies may not know how much you're paid.