Mug

Set one on a table and it counts as a bottle for alchemy, which is the only reason most people make one. Potion rooms usually end up with a bare bottle parked on a surface. A mug does the same job and looks like it belongs in a tavern.

The other use is ale, worth batching if you are building a bar or want the melee buff on hand before a fight. Dropping a mug into shimmer skips the brewing step and just hands you the drink.