calum.org is hosted on a linuxvps.org Linux Virtual Private Server. Why not get your own?
As the browser is one of the most common points of entry into a system, it makes sense to do everything that is possible to secure it.
Any sane user will never browse the web as root (or an account with Administrator access in Windows*), as any malware would then be able to do anything on the whole machine.
* This is insane. If you do it, you deserve everything you get.
So, in Linux, of course I use my normal user account, and trust in the fact that Linux, on an AMD64 processor is fairly safe.