One of the things I've been looking into in my free time is the Microsoft Sync Framework (MSF) (currently in CTP mode). The MSF is: [A] comprehensive synchronization platform enabling collaboration and offline for applications, services and devices with support for any data type, any data store,...
Via ActiveWin : The Microsoft .NET Framework 3.0 is the new managed code programming model for Windows®. It combines the power of the .NET Framework version 2.0 with new technologies for building applications that have visually compelling user experiences, seamless communication across technology boundaries...