In our vintage metal finishing class, our instructor used four cat food bowls to put the express blue solution in. Somewhere out there are four hungry kittys.
Those magnetic trays are very useful for disassembled guns. Everything sticks in them.
We buy those white color roll-up padded shelf liners to line our work benches with (Firearms Repair). That way there's contrast so we can find our parts when we place them down.