Yep - you can grind it up and make up a cooking mix. There are loads of threads in recipes on making cannabutter etc.

I reckon anything up to 30% of the active compunds may be left in vaped duff - worth trying imho.

I tend to use BHO or Butane Honey Oil - its an extraction method using butane gas as a solvent to basically leech out the good stuff and leaf the herb behind. Dangerous though - look up Honey Oil or BHO and you will find loads of info.

Just bag it up for now until you have a $hitload and are ready for a recycle