Ultimachine Split-Spool Hack

I really like the design of a top mounted spool that rides on bearings, such as my Prusa-Top Spool Mount http://www.thingiverse.com/thing:16046 which was adapted from the MendelMax Spool Mount http://www.thingiverse.com/thing:13329 But after finishing my first spool, I faced a dilemna. Either:
1. Continue to buy a new spool for every new filament batch, or
2. Re-wind my empty spools with fresh filament.

Buying a new spool every time not only costs extra, but I felt it would be quite was