I didn't see a general "Why do folders rule so much?" thread, but this one will do.
I do a bike-bus-bike commute, started last Fall, and got a Birdy for the job. Worked out excellent until winter, where snow and ice forced me to run studded tires and I couldn't source 18" studded tires. So I switched to lockup non-folding bikes on both ends of the commute.
Very often, I find an excuse to drop the longer part of the commute and turn it into a drive-bus-bike commute and to lessen that tendency, was recently considering going back to lockup full-size bikes on both ends.
Until today.
There was a snafu with the bus service and the bus I boarded early, with bike stowed underneath, was repurposed into a direct/express bus. No one told the replacement driver I was on-board; no general announcement made that the bus was skipping my stop. So we pass my stop and I ask the driver about it, he gets grumpy and says he will have to backtrack. Those trying to make flights at the airport are not amused. As we are approaching the highway exit for the return to the passed station, I offer to get out at the end of the ramp and bike from there so the driver can get right back onto the highway at the onramp across the street.
He agrees, we haul my bike out onto the traffic island, I unfold it, the bus takes off back onto the highway and I'm off to work no further and maybe closer than if I'd started at the station. Airport peeps were happy to not be much delayed. Everone won, all because of my folding Birdy.
Yay, folding bikes!