Alright, so I'm building a cluster using Ubuntu Server 12.04.
Ubuntu Cloud Documentation does not answer this question- I've read it.
I've also read dozens of whitepapers, all as useless as other fm's.

Questions:

1. Can I run a desktop application from "the cloud" and where can I fund a tut on this? I'm talking like Libre Office (or M$ Office) or something common like that.
2. Is such a thing only possible with a VM server as well or am I missing the point completely; is desktop virtualization like this even feasible?
3. Is cloud computing really only useful for WEB-based apps or storage?
4. What are some free (and good OSS) used to monitor cluster usage and perform bottleneck analysis?

These questions are independent of "how the software was coded". I want to know if I can store the executable on a server and have it run on a desktop or terminal connected to the cluster, using the clusters computing power.

This question is also independent of "what do you really need". I see a lot of other answers getting into needless detail and questioning about the specifics of certain software or what you "really need".

In depth responses are appreciated but not needed- it is enough for me if you just point me in the right direction.

Thanks for the help.