I'm quoting Geoff from Full Race.

NepTune still uses a Honda ECU, yet does not need a blue interface box. My favorite features are:

-5 Bar Map Sensor Support
-Full Throttle Shift Adjustability
-2 Step Launch w/ adjustability (fuel AND timing)
-higher resolition than Hondata (user selectable)

...and traction control (SFWD LEGAL)

Unfortunately NepTune will NOT be sold to the general public. A select few tuners in the country will use this to tune customer's cars. Currently, there are 2 locations, Boosted Hybrid/Evans Tuning in PA and Full Race in AZ.