When i was in college i wrote an economics paper on the idea of securitizing future income streams from individuals and entertainers. It became a reality several times.
Here's the next idea - securitize people's banked vacation and sick days, which are payable when they leave their job at their current pay grade. Especially for city employees who can accrue these forever and might be willing to cash out midway through their career, it's a really interesting calculation. Takes into account the solvency of the employer and your forecast of the increase in salary of the individual.
Hey, all i know is that anything will future or accrued value can be securitized. Especially since this is a liability for employers, why wouldn't they want it hedged?