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couple of days ago, Niels reminded me of VirtualBox (after I toyed around with both VirtualPC and VMWare Player). Coincidentally, my Ubuntu disks arrived too: I already have these disks, but, as the saying goes, these things manage to hide themselves when you need them. All’s well with the new set of disks, I guess.
While the install of VirtualBox went without pains (besides the silly Windows warnings), installing Feisty Fawn didn’t go all that flawless: the LiveCD itself booted nicely, but during the creation of partitions, Ubuntu gave up (to be precise when creating the partions: manually and automatically). The only way to circumvent this is to ENABLE IO-APIC before you start the actual install. After the installation (right at the moment when Ubuntu asks you to remove the CD), close down the virtual machine, set the IO-APIC to disabled and restart in your ‘shiny Ubuntu’. With sound. Yes, really.
The virtual machine’s networking worked like a charm too: during my LiveCD session (pre-install), I forgot which key-combination switched the mouse between hosted and host mode: Ubuntu’s Firefox worked as it was supposed to do: which surprised me, since I couldn’t remember if I enabled the networking for this particular VM.
Update 1: Screenshot added
Update 2: Excellent article about Ubuntu and Virtual Box.