Topic: Auto-retractable insulated bed cover
This is a cover for the heated bed that speeds up the warming process (by 2x for me). It automatically flips out of the way when the bed raises up to print. It uses some sheet cork, a small square of MDF and these printed parts:
http://www.thingiverse.com/thing:48699
Using it, I was able to bring my bed up to full temperature in 9 minutes instead of 20!