It would certainly be possible with an SDK addon, in the form of a custom layout object, but it really would be a drain on resources, at least once you got over ~1000 companies. I really think just training into your users that they link a contact when they create it would be a lot better, it's easy enough to track all newly created contacts and see by Record Creator who didn't bother to fill the field out..
Nick Bohne
Effective Solutions, Inc.