"What is the most effective way to communicate with your team?"
I would say the best way is to use the weekly team mails. You can also send them e cards when you see they have achieved a goal or won in an auction or game. Also when you see that they are signed in take the opportunity to say hello,maybe chat with them for a while from there you may want to exchange skype details phone numbers or even add them to social media sites that you may belong to.
