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You can access the two USB ports from the bottom of the mouse
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Inside the mouse, the hacked up USB Hub
The USB hub was cut in half, eliminating the 3rd and 4th ports to allow it to fit inside the mouse. The thicker yellow and green wires are carefully soldered to the traces that previously went to the 3rd USB port's D+ and D- data lines.
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Another shot inside (hooray for hot glue!)
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One more shot inside, here you can also see the middle click button I replaced (just to the right of the spring)
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Shot of a Flash drive inside the mouse
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The small flash drive/MicroSD card adapter I used inside the mouse
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Powered on with 2 flash drives mounted
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The final product, looking just like a stock G5, but with flash storage!
I actually completed this hack several months ago, but forgot to post it here until now. Let me know what you guys think.
Happy Hacking!
Post-Note: After reading some of the comments I have gotten on HackaDay and LifeHacker, it seems this is what they believe I am doing with my USB Hub Mouse:
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Now that's just silly!
Here is a short video I just took of the mouse being used as I originally intended.