Maybe it's because I used to work at a venture firm, but I'm always happy to hear a founder who's enthusiastic talk for a few minutes about what they're building.
See my above note about using the term "recruiter" to mean anybody who's looking for talent (eg, lead engineer, CTO). Maybe that wasn't clear.
I got it, but talking to a complete stranger on the phone when you are not looking for a job, so he keeps you in mind for an undefined later? Maybe drop in an example, because I don't see how could it work better than just dropping an email which you either delete (and post an obligatory rage-tweet about stupid recruiters) or tag for later if the offer/company seemed interesting.
See my above note about using the term "recruiter" to mean anybody who's looking for talent (eg, lead engineer, CTO). Maybe that wasn't clear.