This is something i found out that is really wierd. If you are using microsoft then you can keep reading; if not, u don't have to.
anyways, in microsoft, u cant name any folder, program, user account, etc "con". Go ahead and try it ur self. it is really wierd. when u try a folder and press enter it justs switches back to its old name. when u try to rename a user account on xp it says The specified account name cannot be used, because it is a reserved name. Please type a different name.
I just find this really amusing. If anyone knows why, tell me why. Anyways, i just find it fun.

Its a leftover from the DOS days, CON is short for console, which refers to your keyboard/monitor.

so, y can't we use it
anyways, it is cool that we can't though

It is pretty obvious why you can't use it---blackice just said why.