I have a new product on 3dprintermods. It’s called the Maghold Build Plate. It’s a magnetic build platform with a tempered spring steel build plate and a Build-tak like layer. This particular model is not for the Zim, it’s designed to fit Makerbot replicators and clones.
I’m working on a version of this to fit the Zim. The Zim version will be heated and interface with the printer for full control. Obviously this is a niche item and I’m only developing it for my own printer at this time, however if anyone is interested in one, please let me know. It’s probably going to run about $89 depending on whether you need the second power supply for the heated bed or not. (they cost about $25 all by themselves).