Yes you could do it easily, and actually could be used as a computer hacking system. You set up a Perl script to run, preferrably as a Daemon, which wakes up once an hour, to check the time, and syncs the clocks. As the set runtime gets close the Daemon would wake up more and more frequently, checking the time, until at the exact time, considering program delay settings, it starts and runs the program.

A sleeping Daemon listening on a socket takes very little CPU. Look at Proc::Daemon