I am a university professor who set up and ran a Drupal 7 site on Linode this fall semester (http://bk4a.com/bit330f2012/>. It was for 30 students. It worked okay; only went down 2 times under heavy (relative) load from the students. I was super happy with Drupal and all I could do with it. I'm sure it can be configured better. Well, next semester (beginning in early January) I am teaching a class (different material) of 130 students. I would like to run this off the same server but have the sites be essentially independent of each other (separate users and files). The old class site will stay up but will never have new users. Every year I probably will continue to expand the site just like this.
I'm sure there will be on-going consulting related to this. Not much, but retainer kind of work, I'm guessing.
Contact me via email if you're interested and would be able to work on this soon; like I said, I have to teach beginning in early January and I still have to add content to the site (obviously). Please put "Drupal multisite" in the subject. Thanks.
-Scott <scottamoore@gmail.com>