If you're more interested in the recycling and reuse aspect than the re-print aspect, you could melt all the scrap filament onto a cookie sheet or into a bar (like in a bread ban). You could then manually work the material, or use a CNC machine to carve out your next thing.
This Youtube video refers to HDPE, but the same concept will apply to other thermoplastics.
This Youtube video uses a cookie sheet and failed prints.