Rest stops on highways...I went into one in Canada, and there was this huge long line that came out of the restroom/washroom/loo and snaked around the food court. There must have been about 100 women in it I figured I could drive to the next rest stop in half the time it would take to get through the door of the potty where I was. As I was leaving, I saw "Additional wash rooms -->". There were only about 10 people in that line. I am NOT making this up. I guess people just see a line and think "If all those people want to get in there, then it's where I want to be."
There aren't ever enough women's facilities, and there never will be enough to completely eliminate (haha) waiting. As for public toilets in general, it would be nice if they were more prevalent, especially aside from rest stop ones. Just try to find one in most US cities at 3AM.
Air Force pilots of certain aircraft have pee bags. I'm not sure about the specifics of the bio-mechanical interface (how it actually attaches), but it's not a catheter - probably more like an undergarment with a funnel and tube.
One day, we'll have vehicles that look like they were designed by H.R. Giger. We'll get into these bad dogs, and much like those scary attack-seatbelts, automatic thingies will extend and attach to various body parts - the brain/computer interface chip, the blood gas regulator implant (only needed for those extra-atmospheric or submarine jaunts), and the seat, lovingly referred to as the 'Torque Chair'. NOT because it keeps you from passing out in spins or Mach 3 U-turns (illegal, but you know everybody does them), but because they were designed by Archie 'A-Probe' Torquemada, who's keeping the family business going.
...or maybe we'll walk a lot more.
However, that will be then and this is now, and now we need more - and more accessible - potties.