Auterra Dash Dyno SPD
 

Does anyone have experience with this product? Seems it has many functions that have been kicked around in the forum.

http://www.auterraweb.com/

Old tele man, I just bought one off of Ebay from Auterra, but I cannot get it to work properly with my Handspring Visor Prism or my Palm T3. I have partial functionality for now. Their tech support did tell me I specifically that the A-300 must have a direct serial connection, and they had to manufacture their own serial cables for most of the Palm series. I sent them pix of my screenshots with the errors, so I hope they can figure it out. Soon. :)

UPDATE! It has taken me 3 replies back from Auterra Support, but at last my Handspring Visor Prism (Palm OS 3.5) and the Auterra A-300 are working happily together. I am even using my original Handspring serial cable cradle, which Auterra did not think would work. I ended up having to download the files from their website, as it seems the files on the included CD are corrupt or something. The A-300 setup is okay, but a little cumbersome as I cannot use the buttons to make selections; I must use the stylus or my finger to make menu changes.
It does display 2 to 5 parameters of your choosing simultaneously, and even works on my CAN bus Dodge RAM. These are in digital numbers, with small bar graphs. There are also two color graphs that can be selected, but I have not tried that yet. I still need to find a way to somewhat permanently mount this thing in the truck so I can really watch what it shows me.
What I do find a little frustrating is...when I leave the DynoScan program to use any other function on my Visor, DynoScan forgets what parameters I was watching on the list and meter displays.
Here is the gizmo I actually purchased: Palm OS Scan Tools - Automobile OBD II Scanner for Palm PDAs I suspect it may be better with the T3 I have, simply because the T3 has better screen resolution. The A-300 requires a serial cable though, and I'll need to buy one from them for any other device I use... More to come as I get better acquainted with this thing.

Yes, as in RS-232 serial. USB/serial does not work with the A-300. The DashDyno you were looking into has its own connector, where the gizmo I bought interfaces with various flavors of PalmOS devices.
Since I have a Dodge, and no MAF, the device does not read MPG. :( I am asking them about stuffing a couple formulas into the software to figure it out. It can't be rocket science since my overhead displays it...