How I Use It
I typically create wiki pages for each class that I teach. I house links, videos, documents, and discussions there. I also have students create pages on the wiki for various topics that are being studied. It's a nice way to put them in a position to create content.
Overall, I like using Wikispaces as a teaching tool. I am going to look at Google drive in the very near future though. Sites are tough to manipulate at times and only one person can edit a page at a time. Other than that, it's a nice, safe place to store and create a lot of material.