Well, I've had my MacPro in Canada, MacPro in Nashville, my MacBookPro on the Road, my iMac in the Office, and my iPhone in my pocket, all syncing harmoniously for the last few years, since .me was .mac

Now... my Canada MacPro has duplicates of everything - Address Book Contacts, iCal entries, Transmit Shortcuts, Safari Bookmarks... it's a real mess.

Just opened my MacBookPro.... same thing it's populated with duplicates of everything... iPhone, iMac (Haven't checked the Nashville machine, cause I'm not there)... but I'm sire it's a mess too, as 4 of the 5 devices are completely populated with duplicates of everything.

Any ideas on the quickest way, to clean this mess?

I've run into this too, Kingfish. Unfortunately, unless you've got a backup that you know is "pristine" and can thus use to overwrite the data on your other Macs, there's no easy fix. Moreover, you're probably gonna lose some data somewhere as you attempt to correct this...

Do you have a primary Mac? One that you generally work on most? If so, I'd start with the data on that one for the apps you list below and get it back up to snuff. Once it's what it's supposed to be, then you should manually sync via the MobileMe Sync option, selecting the "Advanced" button and then the "Reset Sync Data..." for the offending Macs, selecting the "Replace: All Sync Info" option, so it/each is overwritten with the now-correct info.

It won't do you any good now, but after the last time Dotmac/MM jagged up a multi-device sync like this for me, I chose one Mac to be my "primary" device, and have since always manually overwritten the data from it onto my other Macs exclusively, as well as consciously made sure any data changes are reflected in syncs I've performed. That doesn't mean I only enter new/change data on that primary Mac; just that I treat it as the most authoritative repository of info, making sure I routinely sync my iPhone and laptop with it. I like the idea of 24/7 cloud syncing, but it has only proven problematic for me, so I've disabled it.

Another thing I do as a Dotmac/MM user is to use Apple's Backup software. Every week, it automatically backs up the info I want synced across my devices, just in case. Hope this helps!