serial number?

[Golbez 1]

is there a way to make a script to see if there is a unique serial number?

like i know i could make it so someone would have to input one then save it to an ini but i wanted to make it so there was a way so only 1 person could use that serial number at a time..

im sure i would need the script to go on the internet and check a file on some server or something.

but is this even possible?

[rasim 18]

MD5?