The TGetDiskSerial is a VCL component. You can use it to read the serial number of hard disk easily. As we all know, this serial number is unique in the world. So this component is of great use, for example, you can use this serial number to creat an encrypt number. The TGetDiskSerial has already succeeded to get the Serial Number in Delphi5, 6, 7, 2006. Here you can download examples of above development language at this site.