BRIAN Cowen was biting furiously on his lip. He was doing his level best to keep his features arranged in their default expression of surly ennui. He was probably trying to recite the scarier parts of the Budget under his breath. Anything, as long it kept a most disloyal fit of the giggles at bay.

Beside him, junior minister Conor Lenihan couldn't help himself from laughing -- even though being one of the 20 mini-ministers facing the chop later this month could hardly be conducive to merriment.

Meanwhile, across the chamber, hearty guffaws were rising from the vicinity of Enda Kenny, and on the next bench over, a gaggle of Labour deputies were in stitches.

And what was the reason for the most unexpected outbreak of post-Budget bandinage?

While the nation was clamorous with the gnashing of teeth and rending of garments, and while Brian Lenihan was turning slowly on a spit in Pat Kenny's studio, what -- or who -- had transmogrified the Dail chamber into The Comedy Store?

It was the spectacle of Pat Rabbitte snacking on the Greens.

The topic of the debate was, naturally, the Budget, but the Labour deputy decided to digress down a more verdant sidetrack.

He had been struck, he mused aloud, at the level of happiness over the Budget that was shown by the minor partners in government.

"Even the Taoiseach went on television and said he acknowledged there was serious hardship and he took no pleasure in it, and he had a demeanour that couldn't be worse if Clara had lost the county championship," declared Pat.

But he didn't share their cheer and he was in the mood to pick on a variety of Greens, beginning with the most colourful one. Paul Gogarty was first in his sights.

"Some deputies say, 'Deputy Gogarty is a nice fellow, slightly eccentric, rolls around on the floor at public meetings and asks Senator Frances Fitzgerald to tickle his belly, and people give him some indulgence for this.

"I do not think the guy is daft at all, however," reckoned Pat.

"He is the biggest actor in this House, and I think he's been getting away with it."

Then he turned his withering wit on Trevor Sargent.

"This is the man who said he would not lead the Green Party into government with Fianna Fail.

And he didn't -- but he got Deputy Gormley to lead it in, and he went in the back door and re-emerged as the minister with responsibility for parsnips and organic tomatoes," sniped Pat, as chuckles broke out around him.

But Pat was only warming up, and he let fly with both barrels in the direction of Chief Green, John Gormley.

"What's the biggest decision this Government has made since it came into office?" Pat rhetorically asked the rapt chamber.

"Without doubt, it was the €440bn underwriting of the reckless behaviour of untruthful bankers," he said. "Where was Minister Gormley? Asleep!" he said in mock-sorrow.

"He was literally asleep in bed with the phone turned off, and a garda had to shake him up to tell him the two Brians had been up all night and had mortgaged the future of the country to save the banking system."

Across the chamber, one of the Brians was trying to look disapproving over such disrespectful levity. But the Taoiseach was finding it tough going.

And Pat was still in full flow about the snoozing minister.

"It was a Monday night, he had given instructions that his bicycle clips be left out for the following morning with the helmet, because when the cameras are there for Cabinet meetings, you cycle to work that morning.

It's very important, and the two garda cars follow you with the lunch box of Ryvita and tomato," he said gravely, as deputies dissolved into fits.

Alas, all too soon Pat's alloted time was up, and the Leas-Cheann Comhairle was poised to sound the gong. Beside Enda Kenny, Denis Naughten wiped his eyes.

"The Chair should give Deputy Rabbitte another five minutes. The Taoiseach is enjoying himself," he suggested naughtily, nodding over to a guilty-looking Brian.

But wise Pat took his bow and took his seat to a round of applause.

Unlike most politicians, the former party leader knows when to quit the stage. It was just a pity that not a single Green had been in the chamber to enjoy it.

The jollity was all the more startling as it came after a fractious session of Leaders Questions in which the Taoiseach had locked horns with Eamon Gilmore, who put the boot in as soon as he rose to his feet.

"Today and tomorrow we will have an opportunity to have a long debate on the Budget, on the extent to which the Government has screwed working families on modest incomes," he began, as the Taoiseach's hackles began to rise.

But right now Eamon wanted to know more details about what he described as "the plan by the Government to take all the property which represents their bad debts off the hands of developers".

Eamon was in manure-stirring mode.

"Not only will the Government buy back the property these people speculated on in this country, but it also intends to buy back the property on which they speculated abroad, including the shopping centres in Birmingham, the apartment blocks in Bulgaria, the hotels in Dubai and the retirement villages in Florida," he claimed dramatically, waving about a copy of the Government's question-and-answer document on the Budget proposals.

The Government front bench were furious at Eamon's interpretation of this particular proposal, and the usually urbane Micheal Martin almost launched himself out of his seat and across the floor.

"Read on! Read on!" shouted a seething Foreign Affairs Minister, jabbing his finger towards the pages in Eamon's hand.

Brian Cowen let slip a small smile at this unexpected hold-my-jacket moment from Cork's Mister Cool.

Micheal and Brian Lenihan might as well take some of the flying flak too.

After all, sharing the pain -- that's what this Budget is all about, isn't it?