I dont know if you guys already have this on your list or not but here ya go

A Multi-Line ComboBox/DropDownList that if my line item it too large it auto wraps. And the when a users types into the CBO/DDL it will open and jump to the first item starting which the given string.
Maybe even a Paging Feature to allow for you to load only like the first 100 and then when you hit the bottom do the next 100. This would be an awesome control especially in integration with your other controls. I have seen similar ones on the market but i am satisfied with your controls and level of support. Please let me know if you need some links to sample controls.

Hope you can implement something like this. Take Care