Backup Outlook 2000 pst

I am using Windows 98 setup in a workgroup network. I have Outlook 2000 configured to deliver mail to a personal folder file and it is a little over 1 gig in size. I would like to back this file up but I’m not sure of a good way to do this. I can manually copy it to another computer in the workgroup but I often forget so I would like to know if anyone has any ideas how I can back up this file automatically like once a week or so. Thanks.