(This entry is totally unrelated to IKVM.NET)
Last week I got my new ThinkPad T41p and it has a cool feature, a built-in accelerometer. It is used to park the harddisk when the system detects shocks or falls down ("IBM Hard Drive Active Protection System").
I reverse engineered one of the IOCTLs that can be used to read the accelerometer data and built a simple C# application that displays an artificial horizon. It includes a simple reusable class that encapsulates the communication with the device driver (the standard IBM device driver).
Source can be found here.
Not very useful, but fun stuff anyway. In Longhorn this could be used to keep the desktop level :-)