For example if you read the above quote the most obvious comment to make after picturing this poetic gem is this: how exactly does one jerk off by having their thumbs (plural!) up their asses (also plural!)? I mean unless my dexterity is a sub par I think it's pretty close to physically impossible. Furthermore I can't help but feel that if one were to achieve such a physical position, it would be anything but enjoyable.
The other variant of cab driver is the one who wants to know about your life. I once took a cab from work to my train station (a glorious 5 minutes) and within seconds my new black friend/shrink looked at me and said "I don't mean to make any broad claims, but you don't look very happy. You deserve to look happier." There's nothing worse than when strangers tell you something which you already think about once in a while. And even if it's not fully true (I am happy!) it's pretty difficult to disagree when you're in a cab leaving work at 11pm.
The perverse thing is that I spent the ensuing 5 minutes trying to convince the cabbie otherwise and that life, much like roller coasters, has it's ups and downs but in general you're happy you got on the ride because you got on because of your own volition. Now that I think that this roller coaster metaphor is also powerful because you don't really enjoy it as much as you could and when you're older and you go through life/roller coaster your back tends to hurt a lot afterwards.