The symbol for Ångström - the unit beloved of protein crystallographers, probably because X-ray diffraction of proteins is best around atomic (ie Å) level. Just as "nm" means nanometers and "km" means kilometers. Its HTML character entity is & Aring ; (except without the spaces, of course).

The letter å (Å in capital) is used in Norwegian, Danish, Swedish and other Nordic languages. It is a vowel and is pronounced like the A in the English word "ball" or like the O in "storm". It is the 29th and last letter of the Norwegian alphabet. Hence Norwegians say "from A to Å" instead of "from A to Z".

Example of its use in Norwegian:
Må du stå og se på? (Do you have to stand there watching?).

A letter in the Scandinavian alphabets. Pronunciation changes over the centuries, and in the Scandinavian languages some 'a'-sounds gradually slipped into sounding more like 'o'. To clarify this they started writing a small o above the a. This then became the letter å.

Not a letter in ALL the Scandinavian languages, eg. Finnish does not have the letter Å. Since there are a lot of (5-7%) Swedish speaking people in Finland, including me, Finns have to learn Swedish, which does have the letter Å, in school. And the letter Å is usually a little hard for them to learn since its pronounced like a 'o' in Finnish, thus they usually get it wrong when they try to spell something, 'o' instead of 'å' and vice versa. And this of course pisses of the before mentioned part of Finns that DO speak Swedish. Also notoriously difficult to find on a keyboard if your abroad and writing a mail home in Swedish.

Å is mostly used in Swedish, but can be found in Norweigan and Danish too. (I think, correct me if im wrong)

I may be wrong, but at least every Finnish dictionary, ABC-book or classroom poster that I have laid my eyes upon has included the letter Å in the Finnish alphabet:

...X, Y, Z, Å, Ä, Ö

It is a fact that the letter Å is not used in any natively Finnish words, but neither are X, Z or C, all of which can be found in the Finnish alphabet as well.

As the letters "o" and "å" sound the same in Finnish, "å" is generally called "ruotsalainen å" ("Swedish Å").