Where does Edmodo fit in a mathematics classroom?

Last year I was introduced to a web resource called Edmodo at the FETC 2011 (Florida Educators Technology Conference) and then again during a graduate course at UCF (University of Central Florida).  According to my experience with Edmodo, I would consider it a social networking site a lot like "Facebook," but meant to be more educational and allows for teachers to have more control than what "Facebook" would offer.  Although Edmodo has a lot to offer teachers for their classroom, I had a hard time thinking of how I could integrate the use of Edmodo into a mathematics classroom.  This is what I have come up with so far:

Last year, when I first started using Edmodo, I created an assignment for my Pre-Algebra students to research the golden ratio and Fibanocci sequence and find out how the two related.  The students were to present their answers in a Prezi, powerpoint presentation, or movie.  Most of the students chose to either do a prezi or a powerpoint presentation.  On Edmodo, the students were able to load their prezi or powerpoint presentation directly onto Edmodo.  This eliminated the students having to bring in a flash drive or burn a CD with their presentation.  It also allowed me the option to grade their presentations online from home on my personal computer or at school with my school computer.

This year I have found a few other ways to integrate Edmodo into my mathematics classroom.  I have created a library within Edmodo of resources and websites for the students to access if they are struggling with a particular topic from class.  I have also posted links to their online textbook that provides many of their own resources to help students understand the concepts presented in class.  Because of limited time to cover material within the classroom, I often post links to websites that go beyond the material covered in class for students that are interested in a challenge or have an interest in a particular topic.  For example, the other day we were talking about cubes and when I was looking for a picture of a cube I came across an interesting website that taught step by step instructions on how to create a foldable cube.  I immediately added a link to this for the kids to access.  Also, in class the other day we were talking about the Order of Operations and how they use the mnemonic device PEMDAS.  The P represents parentheses.  I thought we should change the P to a G to represent grouping symbols.  I then had the students think of a new mnemonic device to remember GEMDAS and post their idea on   Edmodo.  I then took all there ideas and created a poll for all the students to vote on their favorite.  Lastly, I allow the students to post questions directed to class about what the homework is.  

I feel that I have come up with a few good ideas, but I am more than welcome to hear your ideas.  Oh, and by the way, Edmodo has an option for teachers to link to subject matter groups.  It allows for  teachers around the world to share their ideas.