From my understanding there is an upgraded flasher for the FJ that will do this but it doesn't work with the 4Rs with the DRLs that use the turn signals. Not sure if it would work on the '14+ or not.
Odd thing to expend time and money on, but to each their own right?
I did it, because the 2012 Audi S4 that the wife drives has this function built in.
I thought it was pretty nifty, so I wanted in the WRX.
After it was installed, I ended up removing it shortly after. It never seemed to be integrated fully/properly.
I would not look to do it again, unless the car came factory with it.
Sounds like a easy job for [MENTION=65614]Antman[/MENTION]
My wife's RAV4 has it and I don't like it. It's like a nanny scolding you on how many blinks you must use.