can’t think of anything else. google it. 😛

The largest application of pure silicon (metallurgical grade silicon) is in aluminium-silicon alloys, often called “light alloys”, to produce cast parts, mainly for automotive industry. (This represents about 55% of the world consumption of pure silicon.)

The second largest application of pure silicon is as a raw material in the production of silicones (about 40% of the world consumption of silicon)

Pure silicon is also used to produce ultra-pure silicon for electronic and photovoltaic applications:

Semiconductor: Ultrapure silicon can be doped with other elements to adjust its electrical response by controlling the number and charge (positive or negative) of current carriers. Such control is necessary for transistors, solar cells, microprocessors, semiconductor detectors and other semiconductor devices which are used in electronics and other high-tech applications.

Photonics: Silicon can be used as a continuous wave Raman laser to produce coherent light. (Though it is ineffective as a light source.)

LCDs and solar cells: Hydrogenated amorphous silicon is widely used in the production of low-cost, large-area electronics in applications such as LCDs. It has also shown promise for large-area, low-cost thin-film solar cells.

Steel and cast iron: Silicon is an important constituent of some steels, and it is used in the production process of cast iron. It is introduced as ferrosilicon or silicocalcium alloys.

Compounds:

Construction: Silicon dioxide or silica in the form of sand and clay is an important ingredient of concrete and brick and is also used to produce Portland cement.

Pottery/Enamel is a refractory material used in high-temperature material production and its silicates are used in making enamels and pottery.

Glass: Silica from sand is a principal component of glass. Glass can be made into a great variety of shapes and with a many different physical properties. Silica is used as a base material to make window glass, containers, insulators, and many other useful objects.

Abrasives: Silicon carbide is one of the most important abrasives.

Medical materials: Silicones are flexible compounds containing silicon-oxygen and silicon-carbon bonds; they are widely used in applications such as artificial breast implants and contact lenses. Silicones are also used in many other applications.

Silly Putty was originally made by adding boric acid to silicone oil. Now name-brand Silly Putty also contains significant amounts of elemental silicon. (Silicon binds to the silicone and allows the material to bounce 20% higher.) “