Empty Cans

Are they useful for anything?

Dip (!) them into bottles of healing liquid. It will split the contents of the bottle between itself and the can, effectively giving you two healing potions. Also, liquids in cans won't shatter when fighting Elpuri, Enner Beast, or getting hit by explosions.

If Mellis likes you, he may fill them when you pray to him. Same with empty and broken bottles.

Dip Empty Cans into water fountains, or throw them at people if you're of a high enough level to kill them once they turn hostile. Better yet, get Elpuri to about 1 HP, and then lob a can at him. Post a screen if you can kill him doing this, even if it's in WM.

Done.

Mellis will also replace banana peels with bananas. So hang on to them.

thats a waste unless you are out of empty cans/bottles. there's a lot more food value in a can of banana than in a single banana, plus you never get a banana filled with ommel fluids.

True but the peels weigh almost nothing and I'm pretty sure she'll try to trade cans and bottles before peels.