The Microsoft Surface tablet I picked up on
Amazon Ebay for £310 has a video out port and a USB port too. I happened to have a three or four quid mini HDMI cable lying around here which turns out to be the same as the video out on the thing.
I plugged it into the tablet and the other end into my 24-inch Asus monitor. Then for good measure removed the wireless dongle from my desktop for its Logitech wireless mouse and keyboard and stuck that into the RT tablet too.
The monitor got the signal immediately and, once I told the tablet to extend the display, got the right resolution too. So this was now a two-screen setup. The mouse and the keyboard worked immediately without any drivers. I pulled up Word and IE. They worked fine.
You wouldn’t play games on this and I didn’t check it in detail. But it seemed a very usable home office two-screen desktop to me, albeit one locked to Microsoft Office since the RT won’t let you install any other desktop apps.