Yes, I found that very odd indeed. The fellow was prolly working for Siemens or Ixos, though, and he was afraid his colleagues would see him read anything immature. People try to be very mature and serious when they work for such important companies, and the Paul-oid might have been scared he'd get ostracised for reading Harry Potter.

Should I ever take myself that seriously, I hope someone gently takes me aside and shoots me.

Being recognised for a fellow fan by total strangers is fun. I remember wearing my Slytherin scarf to the amused giggles of passing school girls when the first Harry Potter movie came out. By now, everybody wears scarves that look vaguely as if they belong to British public school uniforms, so the effect has worn off.

I plan to make myself a "Vetinari for President" t-shirt (as in minkhollow 's icon) and shall then see what the reaction is. With all the IT people in my morning train, I hope there will be some funny incidents to report.