TUNIS - At 7.45 am on any given day in the Tunisian capital, you might notice that drivers stuck in rush-hour traffic seem to be chortling away in unison.On Radio Mosaic, the North African country's most popular radio station, it's daily sketch time when comedian Migalo ribs not just ousted Tunisian leader Zine al-Abidine Ben Ali, but all of the Arab leaders fighting for survival in the 'Arab Spring'.Ben Ali's famous last wordsRapper Mohamed Ali Ben Jemaa was the first to seize on Ben Ali's famous last words -- the final of three speeches before he fled on Jan. 14 -- in which he switched to colloquial Arabic.Waving his finger at the camera, he repeated over and over "ana fahimtku" ("I have understood you"), in what appeared to be a speech-writer's deliberate invocation of French leader Charles de Gaulle's famous "je vous ai compris" to French Algerians in 1958 during the Algerian war of independence."Most of his speeches were written in classical Arabic and people didn't understand 90 percent of what he was talking about," said Ben Jemaa, whose rap song quoting bits of Ben Ali is regularly played at weddings and parties."In the last speech, he started talking about things he didn't understand -- democracy, human rights, freedom. It didn't make sense."Ben Ali often talked of democracy and development, but no one dared to ridicule his words publicly until the revolt that began in late December.Habib Bourguiba, seen as the father of modern Tunisia whom Ben Ali deposed in 1987, provided less fodder for humor since he commanded far more respect among Tunisians, Ben Jemaa said."Bourguiba could improvise and was very educated. He would also pull off coups de theatre in public such as weeping. He was charismatic," Ben Jemaa said. "But Ben Ali couldn't talk, he was a dictator who despised the people.""The people want to bring down the regime"Tunisians may go down in history for having invented one of the most ingenious street slogans ever in Arabic.The phrase "the people want to bring down the regime" has been the cry from Morocco to Bahrain.It was the central rhetorical device of the movement that brought down Egypt's Hosni Mubarak in February, and it was the phrase that represented a red line for the rulers of the Gulf state of Bahrain, who crushed their protest movement in March."The phrase came from the oppression and injustice that Tunisians felt and the division that Ben Ali's regime created among Tunisians," says newspaper columnist Salah Attia. "It expresses the idea that the people are united in the desire to bring down this regime that tries to separate us."Part of its beauty, Attia says, is that in its simplicity it bypasses the political rhetoric that Arab governments and the educated elites around them use to shut poorer social classes out of the political and economic systems of the state.It also expresses the idea that the people are actors in creating their own future since the Arabic makes clear it is the people who want to bring down the regime, not that they hope the regime will be brought down by some other, outside force."I doubt many people who went out and asked for a 'democratic system' knew what it meant," Attia said. "But it was an alternative to the language normally used, it was a way of breaking the wooden language built by Ben Ali over 23 years."Political humour is hardly new to Arab countries. A number of famous shows have acquired a TV following in Lebanon, Egypt, Syria, Morocco and others. Theatre has a long history of political comedy, Morocco has a stand-up comic circuit.But limits invariably exist on how far satirists can go.Even now, some Tunisian politicians have expressed irritation at the lampooning unleashed by the uprising.On Radio Mosaic, Migalo also imitates Islamist Ennahda party leader Rached Ghannouchi, centre-left leader Najib Chebbi, often accused of opportunism, and communist ideologue Hamma Hamami.One sketch that centered around a major football match this week encapsulated popular views of them. Chebbi invites everyone to have a sandwich, Ghannouchi tells the players to cover up, and Hamami says he rejects everything, including football.Captain Khubza said he received angry reactions from Ennahda supporters saying Ghannouchi should be left above the fray.So far, one party is indeed above the fray: The army.No comedian has lampooned chief of staff Rachid Ammar, who has maintained a conspicuous silence as an interim government prepares for new elections and a new constitution that maintains Tunisia's secular political system.Ammar is viewed as having forced Ben Ali out by refusing to back security forces as they confronted protesters in January though it is still not known exactly what passed between the two men during Ben Ali's final hours in the country."We satirize everyone," Khubza said, rejecting suggestions the army chief was off-bounds. "If Ammar appears in the news and does something, then it's okay, but he hasn't appeared for months."This week, Ben Ali and Yemen's beleaguered leader Ali Abdullah Saleh, both now in Saudi Arabia, are arguing about the housework."Hey, come on Saleh, I've had enough of this! Every day, I prepare the breakfast, I wash the dishes, and you're lying there doing nothing," Ben Ali complains."I'm ill! I'm ill!" remonstrates Saleh, who left Sanaa for Saudi Arabia last month after he was wounded in a bomb attack.It descends into an argument. "You were ousted!", says Saleh. "You came in an ambulance!" retorts Ben Ali -- before Libyan leader Muammar Gaddafi, battling NATO forces and rebels, calls up to say he's on his way over.Political humour has taken off in Tunisia since Ben Ali's police state collapsed in January, removing in one fell swoop a complex web of barriers, both mental and physical, to free expression.Tunisians are proud that they set in motion a train of popular protest movements across the Arab world that have shaken entrenched political systems and international alliances. Now they see themselves at the second stage of the revolution: satire."Tunisia was a pioneer in revolution and now it's at the forefront in comic expression," says the voice behind a masked Zorro-like character called Captain Khubza, a name meaning 'bread', whose cartoon sketches are issued weekly on Facebook."We are complementing the revolution with this comedy because we don't want there to be any retreat in any way on the issue of freedom of expression."Captain Khubza first appeared in February, brandishing a stick of French bread as his only weapon in the face of Ben Ali's police in his first sketches featuring impressions of Ben Ali, a former interior minister whose extended family developed a mafia-like hold on all aspects of life in Tunisia.