Though it’s still in development, Microsoft have released a tool that allows you to run SideShow gadgets on any bluetooth enabled device that is running Windows Mobile 5 or 6. SideShow has always seemed a little gimmicky to me but I’m sure there are people who will find this useful.
From MS:
Windows® SideShow™ for Windows Mobile® is an application for Windows Mobile 5 and Windows Mobile 6 Pocket PCs and Smartphones that allows you to use your Windows Mobile device as a Bluetooth SideShow-compatible device. This enables you to use your phone as an extra window into your PC. You can both access your computer’s information from your Pocket PC or Smartphone, and control the computer through a gadget interface. While the phone is out of range, or when your computer is off, you can continue to view content sent to the phone previously. This makes it easy to send information to the phone that you’ll need later on.
Here is a YouTube video that shows some of the features etc.
Download the Developer Preview here…
