The Miata Link ECU is a full stand-alone ECU offered by Flyin` Miata (www.flyinmiata.com). The Link ECU has features like datalogging, adjustment on the fly via keypads, laptop or handheld pilots. It also has knock sensing and boost control capability for an added price. The Link or any type of stand alone is vital to make fuel and timing adjustments to the Miata.

The Link is stickered for $1386 at FM. While it may seem expensive, but the Link ECU had proved itself to me over the past 6 months. I was lucky enough to get away with the works for less than $1500. So now I have a car that has knock sensor, EBC and full engine control with datalogging capability.
For those who cant afford a new Link ECU, here are a few things that you might want to consider.
While the Link ECU has a sticker price of $1386, there are a few things you can do to make it a little cheaper. For example, you can take $250 out of the $1386 by not getting the keypad. If you dont use the keypad, you do have to use programs like the PLink. PLink and its misc. parts cost me roughly $150, which is still enough to give me a saving of $100 dollars. I used the $100 on the knock sensor instead.
You can always use the laptop to tune the car. It's more of a hazzle, but you can save money this way too.
Since I got the Link ECU, I removed my FPR, AFM, stock ECU and the Greddy intake pipe. I sold all the parts within 3 days of installing the ECU. I think I got a total of $100 for everything.
The Link took me about 4 hours to put in. It was fairly easy to get everything hooked up. Since I am using the PLink, the learning curve is a little steeper on my part. There are not many people that are doing it this way, I was lucky enough to get help from Matt in KC and Chi Row, who wrote the program. They are both great guys, just like the guys at FM.