Depends if you need it to access local or remote PCs. Localy you should be able to us the AT Service. But if you're trying to access remote PCs (Especially drives in my case) I run into permissions issues. I'm currently using the MS SQL Server Agent / Jobs. Just setup a new scheduled job and have it run the perl script. Works great.
They also make cron services for NT. Like AINTX's. You'll also need servany, or firedaemon for NT. You should then be able to setup that services to use X account for access issues.