Sometimes you have far too many attributes to put them in a list or even a dropdown.
In those cases, providing a list of 10 with a text-box above to type into would make things quicker for users of that site.
Users would type in the text box and the list below will automatically update based on the search query. The user can then click on any of the items.
It would also auto-complete to the most likely search result (the top 1 from the list) and if the user hits enter it would be the same as clicking that top result.