Toll collection. Driving on toll roads is SOOOO much better with electronic toll collection. When I moved to the NYC metro in '95, a drive from Hackensack to Lakewood might take 2+ hours with at least an hour spent just waiting at the tollbooth. With E-ZPass just zoom through at 70mph.
Air quality. I grew up in the Los Angeles basin in the 70s and 80s and remember having to stay inside because the smog was so bad - Stage 2 smog alerts, they were called. Apparently they haven't had one of those since 1988. Haven't had a stage one smog alert since 2003.