Hiya.
I'm working on a project that might be of interest. Its a power to RPM plotter, based on the little Maximite computer. The "device" will let you connect up an alternator so it can read volts, amps and RPM. You then spin up the alternator with a drill, lathe, engine, whatever, a few times from 0 to 1000rpm, and it will then present you with a graphical plot of the power curve, save the data as a excel file, and let you compare it to previous tests. Normally generating such a bunch of information takes hours, you need to find a power source that can hold the alternator at set RPM's while you write down meter readings, without over charging the test battery or cooking the dump load.
This device can do the whole test in a few seconds, with 1 RPM accuracy. Each RPM reading is averaged, up to 100 readings per RPM, so the more you rev up and down the alternator, or the slower you change the RPM, the more accurate the results.
Its based on the Maximite computer, a little hand size computer kit based on the PIC32 processor running at 80MHz, and runs on 12v. The Maximite connects to a VGA screen ( or composite video ), standard keyboard, and stores its program / data onto a SD card. You can log months of data on a 2Gig card. It uses a version of BASIC very similar to QBasic, with a few added commands. Its just like a little TRS80 PC, but a hell of a lot faster. It also has 20 input/output pins, 10 analogue and 10 digital. These can be used to measure volts, amps, etc. Sampling rate is pretty good, I've had it read over 1000 voltage levels per seconds, and I put together a simple CRO program and its displayed the mains hum! The digital pins can be used to measure frequency ( up to 200kHz ) , period, duration, etc, and act as interupts. The Maximite cost $79AU.
I'm putting a page together on my site about using the Maximite for RE related projects, will post the link once its up and going. I think the Watts to RPM plotter will be handy, especially for testing a new alternator and calculating the best turbine to suit it. I've also got a windmill controller/logger that will graph power to wind speed in the pipeline. Having the VGA screen output mean makes it easier to display lots of data at once.
Link to discussion about the Maximite on my site, including links to the designer and supplier
http://www.thebackshed.com/forum/forum_posts.asp?TID=3378&PN=1. I think for its price its a great little bit of gear.
Glenn