There's the new recipe for the quantum suit helmet that requires Iridium Plates, but the old one still works with a -full- Lapatron Crystal. (The one that doesn't require Iridium Plates.)
Also Snowballs stack past 16 in a compressor when you stick it next to a pump, but DO NOT when Water Cells are used in a compressor.
Edit 1:Two stack of snowballs at 263 each right now. I don't think it ends.
Edit 2: At 300 now. Isn't there some point where it'll loop back to 1?