Best Practices in Workgroup Maintenance?

option8 asks: "As the sysadmin for a smallish workgroup (15 or so users) I'm constantly wrestling to balance a regular maintenance regime with the users' continued productivity. As it is, I strive to keep my regular maintenance to a minimum -- optimizing drives, checking for directory and file corruption, permissions repairs, clearing logs, software updates -- after hours, on weekends, or whenever someone goes on vacation. I have a lot of stuff scripted - backups and whatnot go off every night - but there's a lot that requires at least a minimum of my 'monkey clicks the Okay button now' attention. Is this the best way, or do the other BOFHs out there have a better solution to regularly scheduled maintenance for the workgroups/labs/studios they oversee?"