The sequence I've been touting for over a decade:
Tom zings WFMU DJ Hova, followed by his chat with Manny, aka DJ Dragon from Studio 54, and ending with Tom serenading him with B & S's "I Fought in a War" and "The Model".
Originally aired 7/27/2004, but this entire sequence is available via the 12/13/2010 episode of Best Show Gems.
I have a standalone .mp3, if needed.
Another one of my oft-cited calls is the legendary Spike call from 9/5/06, which has a ton of great Abbot & Costello-y stuff, most notably the classic Carroll O'Connor sequence.
The Spike call starts at around 55:53 into the 9/6/06 show. The C O'C riffage (haha!) occurs in the context of his review of Little Miss Sunshine. The key chunk is this:
Spike thought it was a nice, cute movie, and he praised the performance of "the little girl" (Abigail Breslin) and Alan Arkin’s work as her grandfather. Tom hasn’t seen much of Arkin since M*A*S*H ended its run, so he was glad to see him back on the screen. Spike thinks Tom is confusing Alan Arkin with Alan Aldo from President Baseball. Spike reiterates that Alan Arkin is in the film, but Tom doesn't know who that is. Spike is surprised that Tom doesn’t know Arkin from The Russians Are Coming The Russians Are Coming. Tom adds to the confusion by asking Spike if it’s Alan Narkin, so Spike spells his last name: A-R-K-I-N. Now Tom gets it -- it’s the guy who’s in Little Miss Sunshine! Tom agrees that he’s very good. Spike points out that in addition to his acting, Arkin was once a member of The Tarriers, who did "Black Denim Trousers & Motorcycle Boots". Tom thinks this is a clothing company, but Spike says it was actually a song. Spike loses Tom with that one, so it's time to move on. Spike liked the cast across the board -- the mother, played by Jean Colette, Greg Kinnear, and the guy from The Office.
Spike: I always forget his name.
Tom: Ricky Gervais.
Spike: No, the American version of it.
Tom: Oh, okay, yeah, that guy is …
Spike: The 40-Year-Old Virgin, that guy.
Tom: Yeah, Stephen Colbert.
Spike: No. His name is Steve, but that’s not his last name.
Tom: Steve …
Spike: The 40-Year-Old Virgin, but you know who I mean.
Tom: Ah, Steve Richards.
Spike: No.
Tom: No?
Spike: Carol? Carell?
Tom: Carol Stevens?
Spike: No, not Cat Stevens.
Tom: I didn’t say Cat Stevens. I said Carroll Stevens.
Spike: Well, I never heard of her.
Tom: Him. Like Carroll O’Connor.
Spike: I’ve heard of Caroll O’Connor, but I never heard of Carroll …
Tom: He was not in Little Miss Sunshine, Spike. You are mistaken. Carroll O’Connor is in very poor health, and I’m sure could not have done that movie.
Spike: Carroll O’Connor’s deceased.
Tom: Wait, hold on. What?
Spike: Carroll O’Connor has been deceased for a number of years now.
Tom: Oh, good heavens. I didn’t realize. I send my condolences out to the rest of the O’Connor family.
Tom continues to express his sympathy and wants the O’Connor family, in this moment of sadness, to realize that The Best Show is there for them. He welcomes any family members to call and share their stories. As for Little Miss Sunshine, Tom’s only problem was that he didn’t think the family got beaten up enough. He thinks they could have easily had two or three more things flung at them. Tom says the brother who wanted to be a fighter pilot could have also gotten his legs chopped off. Spike laments that it wasn’t that kind of movie. Tom also thinks the family could have been robbed at gunpoint. Spikes point out that [SPOILER] somebody dies in the film. Yes, but Tom thinks it could have been a murder. Tom thought the fact that each family member got completely humiliated at one point was insufficient. If Tom made the film, he would have generated three or four humiliations for each family member. Spike doesn’t like the idea because it doesn’t fit with the film. Tom would have had the family show up at the Little Miss Sunshine pageant and get robbed at gunpoint. When they returned to watch their daughter, they would have been locked out. More tragedy!
There's obviously a lot of Spike calls to pick from, but the above works well as a standalone chunk.
Cannot recall/quickly dig up the episode date at this moment, but the Joe Paterno Call is worthy of consideration:
http://www.friendsoftom.com/forum/index.php?topic=4587.msg93723#msg93723