Wow. Apparently my camera runs DOS.

“FACTOID: Did you know your 10D and 300D run DOS? That’s right. Embedded in the camera is DataLight’s ROM-DOS. In fact, if you use the right tool such as s10sh you can see that inside the camera is an A: and B: drive. On the A: drive reside command.com and autoexec.bat, and most interestingly, camera.exe.”

(The 300D is the “Digital Rebel”. It, the 20D, and the 10D have all descended from the D60, which was based on the 30D…)

*Shudder*