Steve Lush

I've had my 2009 Toyota Highlander Hybrid Limited (black) for over a year and I was wondering if anyone in this forum has any experience with using performance chips or modules. I do not really care about horsepower, just MPG. I used to use a chip when I owned a Ford coupe and it was very effective, I was getting 35 mpg out of a car that only promises 25, though I also used a direct air intake. Anyone who knows anything would be appreciated.