Non DRM Mobipocket format is already supported on the Kindle - just drag and drop.
If you read some of the Kindle discussion groups, you'll see people complaining about "no backlighting", and then a few days/weeks later they will be lauding the fact that it has no backlighting.
DRM is not to prevent other files from being readable on the Kindle.
The Kindle only allows the reading of Amazon DRM-protected content.
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