If its real life collab, for Me some beers and weed helps to relax and connect with the other person on first meeting. They usually show their gear, after some sips of beer everyone starts to jam some tunes or showing some of their work, and then You add Your ideas to their work or other way around, and new track is born.
If its on ethernet, live chat using skype, while creating track together helps for the workflow and building a connection with a person more than just sending files to each other.
Dont have a lot of experience on ethernet collabs tho.