If you’re looking for a way to create an email list or a knowledge repository, use Google Groups! Are you still lost?
Do you ever need to consistently communicate with the same group of people? Consider using a Google Group to create an email list, so you can always be sure to email the same group without forgetting anyone (or adding someone who shouldn't be there). You can even create roles within this group, so some people are able to send and receive emails, but others can edit who is in the group.
If you use a Google Group to manage lots of questions and answers, like a forum, you can use the “best answer” feature. This pins the best answer to the top of the conversation, so new folks joining will be able to see the best response right away. Members of these groups can also upvote and downvote responses.