Cooperation and Collaboration--can it happen between shops?

One of the challenges faced by different Drupal houses is overlap of efforts. For any given client, there may be several solutions for the same problem that has faced other developers. Similar solutions come up again and and again--meaning there is a waste of time and a waste of code. Often code that goes into a client project, it dies in a client project. If code is contributable back to the community, share it. It belongs in Drupal CVS.