HP has the Colligo Personal Edition as free SoftPaq download for the iPAQ H5400 series devices now.
With Colligo Personal Edition software loaded onto Windows-based notebooks, Tablet PCs or handhelds, you and others you come in contact with can instantly communicate and exchange files using the wireless LAN (W-LAN) capabilities of your mobile devices. No need for central access points, servers or Internet connections - Personal Edition creates peer-to-peer collaborative networks on the fly whenever and wherever you need them.
The Personal Edition 2.1 which includes software for Windows Notebooks and Pocket PCs costs normally US$29.95. As a iPAQ H5400 owner, you can download the Pocket PC client for free from HP's software and drivers page.
Cheers ~ Arne
Related Links : [Colligo Personal Edition] [Download Here]