This is for Mac OS X only. Freeware application TimeMachineEditor changes Time Machine’s default once-per-hour backup interval to a more flexible schedule. If you’re noticing significant slowdowns on your Mac whenever Time Machine runs its hourly backup (which isn’t uncommon), extending your backup intervals or pushing the backup to a once-a-day affair with the freeware TimeMachineEditor should help. Click here to download TimeMachineEditor.