Proving en couche today, I had the usual need for something to support the ends. Instead of the often used wine bottles or lumps of wood I rummaged in the recycle bin and came out with an empty 2 pint milk container and an EVOO bottle. After a wash on the outside, I filled them with warm water, made sure they didn't leak and used them as my centrally-heated "bookends". Perfect in our cold climate!
(Apologies if this tip is known already, but I've not seen it.)
Lance