Rare is the laughter that exhausts you. To see local legend Robin Williams perform live, as he did at the 142 Throckmorton Theatre twice this week, is to sit in a chair and laugh incessantly with 300 other people for nearly two hours, with nary a moment to catch your breath, or to wonder if he'll ever pause to catch his.

Over the course of the two shows this week, local notables like Sammy Hagar and Mort Sahl caught Williams' act, and plenty of others have packed into the Tuesday night comedy series, Mark Pitta & Friends, in the hopes that Williams and a host of hilarious comics will make one of their occasional visits to the stage.

A narrative report of Williams' set inevitably will fall flat. Even in these intimate shows, where he is trying out all sorts of new material and half-baked ideas that he might send off to "premise prairie," Williams' stand-up act is a tour de force. So as he gets ready to head Down Under for a comedy tour, let's cut right to it. Here is a tiny sampling of the topics covered by Williams on Wednesday night, mostly in order but by no means comprehensive and without the ability to represent his rapid-fire pace. Enjoy:

• Local residents' lack of facial expressions during moments of great sadness or ecstasy because of Botox
• Whether or not kangaroos fart, and who was the lucky soul tasked with the job of finding out
• The incongruity of Tea Party members on Medicare calling for the government to stay out of their healthcare
• Legalized marijuana – "the surgeon general has determined that smoking this will make all of your music awesome – even Kenny G"
• "What's the difference between tornadoes and divorce in the south? Nothing. Someone's going to lose their trailer either way."
• The possibility that members of Congress could follow the lead of Nascar drivers and wear the logos of all of their corporate sponsors on their jackets
• A portrayal of feisty raccoons – in a Joe Pesci voice – challenging homeowners to a battle
• The sexual exploits of his pug
• His heart surgery, his decision to get a bovine heart valve, and the impact that post-surgery medication had on his digestive system, including the phrase "turd exorcism"
• A lengthy history lesson of the past decade given to a hypothetical person who had been asleep the entire time, from the Monica Lewinsky scandal to the bank bailouts and the BP oil spill
• A retelling of former Vice President Dick Cheney's wheelchair-bound appearance at the inauguration of President Barack Obama – "good luck with the economy, you little African prince"
• Former President George W. Bush's recent stint as a motivational speaker – "it's like having Lindsay Lohan as your guidance counselor"
• The possibility that Sarah Palin was the love child of Ronald Reagan and Vanna White
• The possible dialogue between former President Bill Clinton and North Korea leader Kim Jong Il at their August 2009 negotiations over detained American journalists
• A maniacal, marathon account of former Pittsburgh Pirates pitcher Doc Ellis' hallucinations while throwing a no-hitter while on LSD
• Using Viagra after heart surgery – "it's like a Civil War re-enactment with live ammo"
• A lengthy description of the intelligent design and manufacturing process behind the male and female sexual organs and reproductive system
• Pornography - how slow-motion porn more closely resembles a horror movie, and the potential merits of Shakespearean porn

"What a weird night," Williams said at the conclusion, as if he wasn't the ringleader of all that weirdness. "It's been so strange. Whenever I come to the Throckmorton, I get to the end and I'm like, 'What did we do?'"

Laughed. Breathtakingly hard.