I'm playing with this at the moment and I'd really like to have
a look at the code oschua has if it can be posted.

What i have so far has a peculiarity and I've posted it under another
subject hoping someone could help.

You'll find it with the title "2003 - Userform combobox behaviour".

I think it would be just as good to just sort and populate though. As you
type each letter the selection  jumps down the list  in any case.... And you
still have to actually drop  down the drop down so to speak.

I've done something like this in Access but I use a text box and a listbox.
It's a little bit easier to manage and I was using SQL of course. Also,
using a listbox the selection is always visible so no need to activate a
drop down.

My guess is though that you want a drop down because of space on the form.

If I get any further I'll post an answer but I think your best bet at the
moment is to hope oschua comes up with code.