Can a free asset on the asset store be limited to non-commercial use?

I am planning to submit a tech demo for my AI middleware to the Unity asset store. I would like it to be full-featured and free, but prohibit commercial use (it's a demo, not a free lunch 8-).

Unity's asset store license specifies that I can attach a custom license ("Provider EULA") to an asset IF AND ONLY IF that asset is free. (See http://unity3d.com/company/legal/as_terms).

But I cannot find any example of such a Provider EULA. I'm certain there are limitations to what such a Provider EULA can include. So:

• Can I preclude commercial use?

• Can I even preclude redistribution as part of a free game?

• Or can I say (like Unity with its Free/Pro distinction) that my free asset can only be used if your company makes less than XXX dollars a year?