The brand new iSync plugins version supports cell phones from major manufacturers to synchronize your data using iSync - Apple's hot synchronisation software built into every modern Macintosh computer.
iSync plugins are extremely easy to use, as you see the list of your already configured phones on the Mac and just need one click to activate them for the use with iSync.
You can even use the iSync plugins if you are not working with Address Book or iCal. As long as your personal information management program is talking to the systems' database, like e.g. Entourage, you are fine to sync.