The OnLive Desktop app was recommended by a couple of teachers that I spoke with at the Ohio eTech conference this past week. Since we have one iPad lab to share with multiple classrooms, it's often difficult for students to create content since they are unable to save their work unless they use Notes and email it to their school account since our network is locked. We have tried Google Docs with limited success and have been met with frustration on the teacher and student ends. The OnLive desktop app seems to meet many of our needs:
1) Multiple users can use any of the iPads in the lab
2) Students can create and edit Word, Powerpoint, and Excel documents
3) Utilizes unique student log-in and cloud-based storage
4) Documents can be accessed on any Internet accessible device (desktop or mobile)
I have used the app, and it was a little cumbersome to get used to (mostly due to the smaller touch keyboard that it utilizes), but it looks and operates exactly like a PC desktop. I'm hoping to try it with a group of students in the next several days and report its success and limitations.