As part of my business, I am getting more and more clients requesting that I handle all their hosting for them, while I have my own server for my own websites, I don't realy want to host their sites also.
If there would be sufficient interest, and people would be willing, I may consider organising a dedicated server share. It would be set up under my management, and configured to run xenforo out of the box.
It would be based on a LAMP stack with Centos and Plesk loaded so each user can manage their own site and databases with a server wide nightly and weekly backup of all data. (7 day and 1 month cycles)
Server specs would be aproximately quad core 2.2ghz, 4-8gb of ram dependent on interest and a 100mbit connection.
While larger sites would not be suitable, I imagine such a specced server would be able to comfortably host a fair few xenforo sites as my old server (dual core 1.8ghz and 2gb ram) managed to handle 832 concurent users at our busiest point. My new server specced 2.1ghz 4gb of ram is going to be hammered shortly with an external 5000 user load test and I will see how it handles those.
Users would also need to accept, that intensive addons (mainly chat) would most likely be out of bounds and need to maintain an air of respect to other people in the server share (resource wise) or they would need to be removed.
So let me know if your interested.