You can record video on your 1000D, 450D, 40D, and 50D through a USB cable to your computer. It works through liveview on your camera.
Update: Now theres a new project called eos-movrec. We did a little field test on the go. Have a look!
This video is from Mike Pan flickr.com.
A gentleman from russia made a fix for the Canon 450D, but with a lot of limitations. I contacted him, and he told me he discontinued the project. An example of this fix, you can see on youtube.
A developer called "Dataghost" at this forum is working with a similar fix for the 40D. It is not available for download yet, it will be finished "when its finished", states Dataghost in the forum.
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