[GLLUG] Virtualization Questions

[Chick Tower]

Since I may someday have a PC capable of running virtual PCs, I've been 
wondering about it.  I know I could read up on virtualization on the 
internet, but I thought I'd take the opportunity to boost traffic on our 
little mailing list.

Are there ready-made guest OS packages available, or do we have to 
create our own?

To create a guest OS package (or container or whatever the nomenclature 
is), is it necessary to create an empty one and then install an OS, or 
can you clone an existing OS installation?

Is it possible to modify the saved version of a guest OS (such as for 
software updates or configuration changes), or would you have to create 
a new saved version?  I realize allowing the guest OS to permanently 
modify itself could be considered a security risk (although 
normally-installed OSes do it all the time), but it would be convenient.

Can a running instance of a guest OS save data in external filesystems? 
  If so, can those external filesystems be simply mounted like any 
other, or would it require some trickery?

I do not yet need to know the details of how to do the things I've asked 
about.  I'm just curious as to how flexible virtualization is.
-- 

                                Chick