Pendelous type threads

So I know I can’t be the only one with this problem, but it’s kind of embarsing espically for someone like me…

How do you keep mulitple computer somewhat synchronized with contacts?

I know it’s stupid but hear me out… I have a blackberry Pearl and before that a Treo 700P that I sync’d at both home and work.  Syncing the treo at work and home caused me some problems, namely that my business contacts polluted my personel contacts and vice-versa.  Now I dont have much a problem with this but I don’t want the next great internet worm to come out of one of my computers and take down several large medical imaging device companies.

Not that it would happen I’m just saying…

So what do other people do with multiple computers and contact lists that they want on all of their computers?

I’ve thought about using google as my “master” archive and then feed down from there but that seems less then elegant and the more stuff I can keep off the cloud the better.

Oh and don’t forget I’m multi platfrom too… I use windows and mac and linux… I don’t care so much about linux, it’s more mac and windows I’m after.