Well, I usually use a trigger to run a script. I usually combine this with a timer to ensure that the script is executed the proper number of times.
This is helpful for people that don't have access to cron jobs.
Basically, in every page of my website, my script would check to see how long it has been since the last time the operation had been executed and if the amount of time since the last execution was longer that the required interval, the operation is then executed then. Otherwise, it is not.
When the script is execute, the timer is reset and if more than one interval has passed, the operation is executed however many times it should to get current.
This way your web server is only working when you have visitors.
There are a few topics about this on the forums if you want more information.
vujsa
Comment/Reply (w/o sign-up)