I wish I had one favorite because it would make it easier to answer this question. I have lots. My favorites tend to be the same as everyone's - when we started a favorites page we ended up with five pages and dozens of shows.
I like the episodes where we try stuff that's new, stuff that's hard. This Week, 20 Acts in 60 Minutes, the episode on an aircraft carrier (which along with our Habeas are arguably the two funniest hours of broadcasting about the War on Terror; Habeas our goal was to make a show about the writ of Habeas Corpus that a normal person would be able not just to tolerate but actually ENJOY). Testosterone's another I love. And - the hardest episode of all - not a listener favorite I think but definitely one of mine, is Stories Our Parents Pitch where every act was pitched by a staffer's parents.
On his least favorite episodes:
Too many to name. Death to Wacky. Secret Life of Daytime. Million Bubbles. In those we aimed high and failed. The Adventure stories in Adventure! Julie Snyder and I just got into a conversation disagreeing about 2010 which aimed high and I swear hit the mark and she says sucks. Idea of that one was to do a show at the start of the year, not looking back at the previous year like everyone else does, but predicting actual things that would happen in the coming year. I love Shalom's story in that.
And on whether he has Carl Kasell's voice on his home answering machine:
Heh. No. I think it's actually a little cheesy that that's the prize on Wait Wait. I think they should give out a copy of the Encyclopedia Brittanica or something if you win.