Yeah, I've actually got an Nlite-ed copy of XP I've burned that I could use, and I almost pulled it out when I first installed XP on VirtualBox, but I've been so happy with vanilla XP on Virtualbox on Linux Mint that I've not felt the need to dig it out. But if you have less than 4 GB of RAM or so, and you plan to run something like Photoshop on XP via Virtualbox on a Linux host, it would probably be a good idea to use Nlite.