Even glider pilots use them to calculate best-speed-to-fly (between thermals): http://www.126association.org/glideslide.htm It takes a cool head to: navigate, aviate and run the slide rule accurately all the while remaining aloft without an engine and merely a glide ratio of 12:1!
Pilot here(private pilot, anyway), and yes: we use the E6B a lot when we're up there. It's nice that avionics can give us things like true airspeed and fuel burn rate instantaneously, but that's only as good as your power source is when it's working correctly. An E6B will never suffer from electrical failure.
I also confess to trusting these whiz wheels ("kakkara", we call them in Finnish), a clock, and my thumb on a map way more than I do trust GPSs and glass cockpits.
Even glider pilots use them to calculate best-speed-to-fly (between thermals): http://www.126association.org/glideslide.htm It takes a cool head to: navigate, aviate and run the slide rule accurately all the while remaining aloft without an engine and merely a glide ratio of 12:1!