I can't remember exactly were but i think i read about this little trick somewhere. You know when you scroll over a file and it will show you how large it is? I read somewere about a cmd trick that can change the size that is shown when you do that. Sadly, i can't remember how to do this.
u can use the cmd prompt to create a file any size u like, and i assume this would show when u hover ur mouse pointer over it. It works by taking a file - say a 10kb .txt file - and adds a sort of padding to the end of it to fill the file out to the size u specified (like 10mb or whatever). I can't remember the site I read about it on, but I found it through google, so with a little searching u should be able to find it