New Look-up control that combines the 'Suggestion contains' and 'Combo'

For some of the fields in the application I work on it would be nice if I could use the best of both worlds ('Suggestion contains' and 'Combo').

So I want to be able to select a value from a Combo list but also be able to enter a string into the field which is contained in one or more of the items listed in the Look-up.

Example:
Field with look-up to city names: Amsterdam, Den Bosch, Groningen, Enschede, Apeldoorn and Utrecht. Then I can use the drop-down / Combo to select one of the cities. But I also would be able to put in 'sch' and find Den Bosch and Enschede and select one of them.