One of the Window (Live) Messenger features that has snuck up on me of late is the P2P file sharing feature built into the product. I suspect that this is part of the technology acquisition that Microsoft go from FolderShare.
I’ve been using it quite a bit lately either to exchange the odd file with my co-workers, for example, last week Geoff was having trouble finding the PowerShell download on the Microsoft site so we just synced it up over messenger.
I think that as time goes by business will start to rely on these mechanisms to allow users to exchange and work on sets of files together legitimately. This will challenge some organisations who have been decidedly “anti-file sharing tech” because doing stuff that breaks the file sharing mechanisms could be quite illegal – if it isn’t already.