Given the background description of some cooking related query, summarize the question into a title

I bought a hand crank can opener (Oxo) because of the good online feedback and only use the "shake" dry approach. It quickly developed rust in between the metal. If I invest the time and scrub, I can remove most of the rust.When I initially posed the maintenance question in IRC concerning rust and utensils and kitchenware in general, I got suggestions from "spend a little on a decent one" to "you want stainless steel". I stored both answers as helpful for future purchases.Just recently I noticed two can openers in the office pantry that both show rust. Obviously these were neglected and showed more corrosion. After seeing this, I am curious if rust is actually normal and harmless. Are there more expensive stainless steel can openers that are rust resistant? Should I be drying more rigorously? I just thought of another possibility: should I keep the can opener in a jar of cooking oil?
What is the proper way to maintain a can opener?

When we make polenta, we use polenta leftovers for lunch, grilling them.Are there any other uses for polenta leftovers?
What can I use polenta leftovers for?

I guess it can be subjective according to tastes, but some reduction is required. If I could know what I am trying to do away with in the reduction process (alcohol, raw bite or volume) then I could adjust according to my subjective taste and dish.Some general guidelines about how do you know when your wine is reduced or what to look for in a reduced wine would be useful.

How do I know when my wine is properly reduced?

