Not on this board but featuring many SDMB regulars were the series on religious beliefs at the Pizza Parlor.
Stealing Esprix’s idea unabashedly (what are running mates for, anyway? ;)), I opened a thread where cmkeller could respond to questions people wanted to Ask the Orthodox Jew. This became so popular that it was continued to a second thread, Ask the Orthodox Jew, Part II, with a OP by the dreaded Danielinthewolvesden.
Kirkland hosted an Ask the Catholic thread, which also went to Ask the Catholic 2: The Wrath of Khan.
Satan, posting under his Pizza Parlor name of NYCNative, invited us to Ask the Unitarian Universalist.
I myself started Ask the Liberal Christian.
And to round out the mix, we had Ask the Mainline Conservative Protestant and Ask the Orthodox Christian (or, Call me a joiner).