As you may know, CF 2.0 implements COM Interop which means you can finally access your favourite COM components without going through the hassle of writing managed wrappers using P/Invoke (or buying a 3rd party component...).
One of the most popular things to use here is of course ... Pocket Outlook. Use the POOM through COM Interop - done! Of course you need a POOM type library, and that's the hard part for most people. So the Windows Mobile team recently posted about this and provided a download link to a PIMSTORE.IDL, which however is broken (today). Therefore I provide you with a ZIPped PIMSTORE.TLB + PIMSTORE.IDL which (the former) you can use in VS2005 to directly add a reference to it and automatically create a RCW. Have fun!
(Please note that this is provided "as is" - use it on your own risk. We do not provide any support for it.)