smart dropdown list

hey there;

using asp.net (vb), i was wondering if anyone knows of some code that can select a record from a dropdown list depending on what the user types in.

for example, if i have a list of countries and the user types an "s", a normal dropdown will immediately take you to the "S" section of the list.  what i'd like is if the user types in another letter ... say, an "a" ... it will take the user to the section that starts with "sa" ... and if the next letter they type is "m" it will take them to the first word that starts with "sam" ... and so on until the user clicks submit.

anyway, not sure if that's possible ... never seen it anywhere but would be interested if anyone has some insight for me.

p.s. i'll double points for the solution if there is one.

thanks all.