Some caveats as the device needs to be Java enabled, wifi/connected but an interesting piece of software.  You need to register for an invite as it's in Beta and no guarantee of getting in.  Pretty cool though.

Link 

ThinkRemote™ Bringing Windows® SideShow™ content to everyday devices Sign Up Now (Community Edition) ThinkRemote sets Windows SideShow content free, bringing SideShow gadgets to everyday electronic devices such as mobile phones, portable game consoles, and remote controls. With support for wired, wireless, and Internet-based connectivity, ThinkRemote keeps you connected to your PC and your content anytime, anywhere. So change the music on your PC, view your vacation photos, or navigate a PowerPoint presentation using your phone. Or a PlayStation Portable (PSP). Or a Nintendo Wii. Or your web browser at work. With expanding device support and compatibility with standard 3rd-party SideShow gadgets, the possibilities are unlimited. Use ThinkRemote with devices you already own Take advantage of the full capability of your Windows Mobile phone or Apple iPhone. Take a break from games and browse your PC's music library on your Nintendo DS or Playstation Portable. Or go for the big screen, and use your Nintendo Wii or Playstation 3's web browser. Whether you're at home or at the office, ThinkRemote lets you access your SideShow content and interact with your PC from anywhere. With built-in support for ThinkConnect, ThinkRemote even takes away the headaches of firewalls and related technical problems.   Works with standard SideShow gadgets Photo viewers. PowerPoint navigators. Stock, weather, and news feeds. E-mail, calendar appointments, and Media Player control. Compatible with standard SideShow gadgets (including 3rd-party gadgets), ThinkRemote gives you what you want where you want it. ThinkRemote works in coordination with the standard Windows SideShow control panel applet. Mix and match with non-ThinkRemote devices without worry.   Integrate with your Z-Wave® smart home (Standard Edition) Look for ThinkRemote support in your Z-Wave remote control. Then dim the lights, adjust the thermostat, or just enjoy whole-home range and navigate SideShow content on the remote's display. ThinkRemote Standard Edition even has built-in control of Windows Media Center™.   Manufacturers: add ThinkRemote support to your devices (Standard Edition) The ThinkRemote platform empowers PC and accessory manufacturers to create mass-market Windows SideShow-enabled remotes and devices. With support for Windows Media Center, IR bridging, Z-Wave, WiFi, and Bluetooth, and with built-in extensibility, ThinkRemote is an easy choice for manufacturers. Manufacturers: click here for more information on the ThinkRemote platform. Sign up for ThinkRemote Community Edition (beta) Which devices will you use with ThinkRemote? Windows Mobile phone or PDA Apple iPhone or iPod Touch Java-enabled phone Sony Playstation Portable Nintendo DS Sony Playstation 3 Nintendo Wii Web browser Computer Skill Level Beginner Intermediate Expert Email address NOTE: This is an application for a beta test program. Invitations will be awarded on an ongoing basis and not all applications will result in invitations to participate in the test program.

Some Details on Sideshow from MSFT

Windows SideShow

Windows SideShow in Control Panel.

Wouldn't it be great if you could read an e-mail message, confirm a meeting location, or check a flight reservation without turning on your computer? What if you could check the program guide in Windows Media Center by using a display that's built into your remote control? Windows SideShow puts this information literally at your fingertips on a wide variety of devices that can retrieve information from your mobile PC or desktop computer.

Windows SideShow is a new technology in Windows Vista that supports a secondary screen on your mobile PC. With this additional display you can view important information whether your laptop is on, off, or in sleep mode. Windows SideShow is available in Windows Vista Home Premium, Windows Vista Business, Windows Vista Enterprise, and Windows Vista Ultimate.

Windows SideShow uses gadgets, convenient mini programs, to extend information from your computer to other devices. Gadgets can run on a Windows SideShow–compatible device and update that device with information from your computer. Using a gadget, you can view information from your computer regardless of whether your mobile PC is on, off, or in the sleep power state—which can save you both time and battery life.

Choose gadgets and customize settings in Control Panel

Windows Vista contains a central location in Control Panel called Windows SideShow where you can turn gadgets on or off for each of your devices.

From Control Panel, you can also set your computer to wake periodically (such as every hour) so that all gadgets that are turned on can update your devices with the latest information.

Windows SideShow: Not just on laptops

Windows SideShow in picture frame.

Windows SideShow–compatible devices can take many forms. Hardware manufacturers are already including secondary displays in their designs for mobile PCs and devices such as keyboards, mobile phones, and remote controls. The following are a few examples:

• Integrated devices on computers. If your mobile PC has an integrated Windows SideShow–compatible device, you can view your Windows Mail inbox without so much as opening the lid or turning on the computer so you can quickly access your recent e-mail messages virtually whenever and wherever you want.
• Mobile phones. With Windows SideShow, you can configure a compatible mobile phone to show you your contacts and calendar, the latest updates from your favorite websites, your favorite pictures, and other information.
• Media remote control. While you watch TV with your family on Windows Media Center, you can find out what programs are showing next or schedule a recording for the next day. You can also browse through your Windows Media Center music collection from the display on the remote control without turning on the TV.

Laptop with in-lid Windows SideShow display.

Some product features are only available in certain editions of Windows Vista and may require advanced or additional hardware.