Mash Tun insulation

The last discussion I found on this subject was in 09. Has anyone found a great way to insulate the mash tun. Maybe even something that is fire proof?

I use a cooler and batch sparge but I wonder if rockwool insulation might not work. you would have to clad it in steel sheet or aluminum but…

Wool blanketts ;D

neoprene - I got some wholesale from a foam supply website

What do you use for a mash tun? That will at least give people an idea what your options are.