Yes Tom, the motor in the hard drive is a stepper motor and it will produce voltage enough to light up an led.
Last night my neighbor asked me to see if I could do something with his computer. I got it working. On the way out to go home he gave me an old IBM Thinkpad 770 laptop with a cracked monitor. Apparently it had been dropped and the screen was fractured.
Not knowing what else to do with it, I took out the hard drive this morning and dissassembled it with the idea of using it for a Tesla Turbine for this project. 4 GB IBM model DTCA-24090 E182115 HG. Rated 5V 500mA.
I never had one of these things apart before, but this looks good and solid. Nice metal platters (Some HD platters are plastic).
The drive motor is built right into or around the bearing in some way. I wondered if it were used as a Tesla turbine, could the motor be used as a generator ?
I found this video - so I guess the answer is yes:
Though I think the spacing between the platters will need to be reduced. It seems that less than 30 thousandth of an inch (0.016 - 0.030) is generally recomended depending on diameter, fluid velocity etc. Since this is a small laptop hard drive closed is no doubt better.
As is, the platters look to be spaced about 1/8 inch apart or about 6X more space than recomended.
Here is something else I found that looks like an interesting idea:
Towards the end of the page under "Optimizations:". Using an "Air Amplifier" nozzle.
Would this boost power to the Tesla Turbine?
Unfortunately the writer's conclussion is: "efficiencies: YTBD..." That was in 2008.
Interesting idea though as these nozzles are supposed to increase air flow by up to 25 times over input. Some sort of vortex phenomenon.