UNIX Emulator?

Misticles

Is there such a thing?

I'm studying for an exam but I am on site and don't have access to the server that I would normally use in work.

Is there anything that I could type the commands into without being connected to a data server?

AnCatDubh

You could go for a "live" distro which would boot off a USB memory stick without making any change to your computer. You could do worse than to start here http://www.pendrivelinux.com/

Alternatively, take a look at www.cygwin.com/ It runs under windows/is quite good and is quite extensive at having unix commands run under a windows command prompt.

Redisle

Booting from a live distro is probably your best bet to be fair. Cygwin is another option but assumes you have admin rights on whatever machine you are installing it on. Is is also quite a large download IIRC, 1gb+.

Another option would be to get yourself a vps. (Virtual Private Server). There are hosting sites based in America where you could get one for ~$5-10 a month. That's basically a linux virtual machine running on a server somewhere that you can access using ssh. Commonly used for web hosting and what not but can also just be used to mess about in linux. Advantage here is that you can access a Linux environment from any machine as long as it has an ssh client so very useful if using client machines with limited privileges.

henbane

You could use something like virtualbox but cygwin or livecd are probably a bit easier