"Time Machine Tip "Back Up Now"
One of the time machine features I hate is the hourly backup that fills up the external hard drive very fast. (? I asked if he frequently have a large amount of file changes - see his reply below in an update - Entourage mail user which can have huge database files that of course are frequently changed/updated.
(As a FYI, if you see huge TM incremental backups for no reason - use the console to check for TM ("backupd") log errors related to corrupted files (error -8088) If so exclude those files.)
I also have been turning on TM only once or twice a day for the last few weeks, rather than leaving it on all the time. At times I have also seen System log entries on "thinning" of TM backups, even with 250GB free on the backup volume. (And TM is designed to remove oldest backups as needed if backup volume is almost full.) After about 3 weeks of TM use with an AL iMac drive with 84GB used, the TM backup drive total size is appx 95GB. (Not using Entourage or Aperture on that machine however.) There's 3rd party utils to modify TM's backup schedules (such as free TimeMachineScheduler that can change the interval to every 12hrs for instance), although I've not used them personally as I try to minimize the number of system mods installed. But I didn't know about the "backup now" feature until now.-Mike)
For this reason, I keep the Time Machine OFF until I am ready for it to do a backup. The problem is when you turn ON the Time Machine, it sleeps for about an hour or until the next scheduled backup. (It can be just minutes depending on when you turn it on relative to your existing timing schedule.) The System Preferences/Time Machine panel does not have a back up now button or option so you have to wait.

Thanks to tip I found buried in one of the Apple discussion topics, I can now leave the Time Machine set to OFF. When I want it to start a back up session, all that is required is to Right-Click on the Time Machine icon on the Dock and select "Back Up Now" from the list of options. (Aperture users - see reminder below. -Mike) I have been using this option once a day for over a week and it has been working great.

I have no idea why Apple hid this very cool option under the dock.
My personal backup preference is SuperDuper; however, is still being updated (slowest update ever) for Leopard.
-Dick"

I thought my 10.5 install DVD came with a printed manual but can't find it to see if the tip was noted there, but after searching, I did find it in a OS X 10.5 help item on TM and in this doc on Backing up files with Time Machine.
And while on the subject, as mentioned previously, Apple suggests Setting Time Machine to exclude Aperture library from automatic backups ("Running Time Machine backup or restore operations while Aperture is running may lead to inconsistencies in the Aperture database") and the same probably applies to any large/frequently changing file such as VM/swap files if you're running Fusion, Parallels Desktop, etc. (And why backup VM/Swap files, which can be very large.)
Update: Dick replied with more info on his comments about hourly TM backups filling up his backup volume:

" As a Microsoft Entourage user my TM drive will fill up faster than others because the way Entourage stores its email. The entire email database will be backed up even when only one email changes. This is why I do not care for hourly backups. Some Entourage users are excluding the database from the TM and then every few days go in change it to get a new backup. This was the discussion topic where I learned about "Back Up Now" button buried in the TM dock. I leave the TM OFF and use the secret button when I want the TM to run and don't have to mess with excluding Entourage.
-Dick"

Now I understand the original comment about hourly backups taking up a lot of TM space. (Even after deleting a ton of old mail and compacting, my mail db file on the PB using Entourage was about 1.1GB IIRC.) I used Entourage X on a PB G4 and liked it better than OS X Mail, which I use on the iMac w/10.5.1/Time Machine. (I checked and OS X Mail doesn't use a single DB file for Mail.)
BTW - Speaking of Entourage (applies to Outlook for OS 9 also) - a year or two ago I had problems with backups of my Entourage mail db file (a read error - would not back up/copy the file) I fixed that by compacting the database. (Option key held down when starting Entourage - after completing and verifying OK, you can delete the old db file.)

" Mike, AMUG has posted a review of the FirmTek SeriTek/5PM SATA PM enclosure. The SeriTek/5PM provides excellent cooling results while offering a quiet, ultra-small, 5-bay, SATA PM enclosure footprint with a unique direct backplane design. The review displays storage performance results of the SeriTek/5PM with the Apple MacBook Pro, PowerMac G5 and Mac Pro computers.
Have a great weekend, TEAM AMUG"

"Temporarily removed the Hitachi 0A35155 1.0TB from the specials page (price was $305 - temporarily sold out). Have Seagate ST3100430AS 1.0TB (7200rpm/32MB cache) now at $309.00.
$2.95 for ground, $7.95 or less for 2nd day air within 48 continental USA.
Best Regards,
Lawrence R. O'Connor
Other World Computing"

There were also some minor price cuts on the specials page for MacBook/MacBook Pro/Mini SODIMMs.

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