It's mainly for sulfuric acid, which breaks down food. But it also has many other uses, like cement fortifying.
jewelery, medical instruments
It's used for jewelry and hair removal.
It is often used to prevent corrosion of other metals and is used in many alloys. Source: http://en.wikipedia.org/wiki/Tin
Lithium is used to make lithium-ion batteries, and lithium carbonate is used as a medication for bipolar disorder.