Alphabetical drop-down list

Hello everybody,

I want to know if this is possible:

I would like to create a drop-down list able to show the available options while one is typing the word.

That is, lets say that the first letter of the word is "a"; well then the drop-down list should be able to show all the stored words begining with the letter "a". Then, if the second letter of the word is "b", the drop-down list should be able to show all the stored words begining with "ab"; and so on.

Is this possible, and in such a case how can I achieve my intent?

Thanks.