* Grillo's deputies all in their twenties or thirties
* None have previous experience in parliament
* Are mostly pragmatic, shun ideology
* Grillo may find it hard to control them
By Francesca Piscioneri and Gavin Jones
ROME, Feb 28 (Reuters) - Meet the Grillini. They are the 162 very ordinary people who are now regarded with trepidation by financial markets and world leaders after this week's Italian election failed to produce a government.
The Grillini - literally "little Grillos" - are the lawmakers elected for the anti-establishment 5-Star Movement of comic Beppe Grillo, which upset all forecasts by emerging as the largest party in Italy.
They now hold the key to the future of the euro zone's third largest economy and possibly of the single currency as a whole, amid fears that Italy's political instability could re-ignite the region's currently dormant debt crisis.
It will be very hard for Rome's hung parliament to form any government without their consent, but they appear to be neither rabble-rousers, demagogues nor even populists, three accusations often levelled at their leader.
Like the movement's mayors and councillors who already run city and regional governments, they seem far more pragmatic than Grillo, whose proposals can become more and more extreme as he whips himself into a hoarse-voiced frenzy at his rallies.
"The ideologies are finished, ideas aren't right-wing or left-wing, they are good or bad," said Sebastiano Barbanti, a 36-year-old marketing strategist elected in the poor southern region of Calabria.
Barbanti told Reuters that 5-Star's "model" should be the kind of policies pursued by its regional councillors in Sicily, who gave up 75 percent of their salaries and pooled the money saved to provide cheap credit to small businesses.
It remains to be seen whether Grillo's lawmakers are dangerous, but the 108 lower house deputies and 54 senators certainly seem like aliens in the stuffy, gerontocratic world of Italian politics.
All of the deputies are in their twenties or thirties and none have any experience of professional politics. Those spoken to by Reuters had voted for the left or abstained in previous elections.
They reflect Grillo's promise to select "normal people" rather than the mixture of career politicians and celebrities recruited by most of the other parties.
They are teachers, students, factory workers and housewives; doctors, nurses and engineers. Several are unemployed. They will refuse the title of "honourable" normally reserved for parliamentarians, preferring the plain "Mr" and "Mrs".
They were selected as parliamentary candidates in primaries held on the Internet, where they were voted on by party supporters after introducing themselves with a written biography or by using a webcam.
Grillo's whole movement, which he founded just three years ago, is based on the Internet.
It has no headquarters, no local offices and no internal hierarchy other than that Grillo is its undisputed leader. And he even rejects this definition, describing himself with some irony as merely its "spokesman".
His followers are certainly inexperienced, but they also say they are determined to bring desperately needed transparency and honesty to the corridors of power.
Their priorities do not however include a referendum on Italy's continued membership of the euro, the suggestion of Grillo's that most worries markets.
His disciples expressed no anti-euro views and played down the referendum idea, which does not feature in the party's manifesto, as just a way of provoking debate on an often taboo subject.
Instead, they all want to change Italy's dysfunctional electoral law, crack down on corruption and waste, cut spending and find ways to offer cheap credit to hard-pressed firms and a minimum income to the unemployed.
Carla Ruocco, 34, who works in state tax offices in the central Lazio region, said she and her fellow deputies would collect just 2,500 euros ($3,275) per month, compared with the standard lawmakers' salary of around 8,000 euros ($10,500).
"The first thing I want to do in parliament is to reduce what Italians have to pay for their political institutions," she said.
Riccardo Nuti, a 31-year-old computer technician elected in Sicily, said reforming the electoral system that resulted in the current hung parliament, and legislation to curb corruption and conflicts of interest were his top priorities.
But for all their zeal, the challenges facing the army of political novices are daunting and it could all end badly. Their opponents on both left and right, as well as in much of the media, will be working to ensure that it does.
First the Grillini will have to take a crash course in parliamentary rules and discipline, choosing their whips, spokespeople and members of committees without squabbling among themselves like the "normal" parties they despise.
And then it remains to be seen how long their morals will resist the murky temptations that come with power. Will they change the system or will the system change them?
KEEPING A GRIP
An often cited comparison is made with the pro-devolution Northern League, which burst onto Italy's political scene in the early 1990s on a crusade against waste and graft but has itself been humbled by series of corruption scandals.
The 5-Star lawmakers dismiss the comparison, saying the League was really about discrimination against the poor south, and that by quickly allying itself with media tycoon Silvio Berlusconi it showed it had little interest in morality.
"With 2,500 euros a month, because remember we are giving back the rest, there's no danger of us going into parliament to get rich," said Laura Castelli, a feisty 26-year-old tax consultant who was elected in the northern Piedmont region.
With his ferocious invective against the greed, waste and corruption of Italy's political and business elite, Grillo is undoubtedly responsible for the party's success.
Yet the shaggy-haired 64-year-old comic did not run in the election and so will not be joining his followers in parliament.
This could make it more difficult for him to keep a grip on his lawmakers.
He showed his authoritarian side two months ago when he expelled two party members who bemoaned a lack of internal democracy and flouted the movement's rule not to appear on television talk shows.
If he should expel any of his parliamentarians from the party they can easily move to a rival one on the left or right where they are sure to be welcomed with open arms.
And difficulties could arise very quickly over the question of whether to do a deal in parliament with the centre-left to allow a government to be formed.
Grillo has ruled out any formal alliance, saying the party will only support proposals it agrees with on a case by case basis, forcing the centre-left into an unnatural left-right coalition with Berlusconi if it wants to survive.
But his position has already been criticised by many supporters on the party's blog, its main forum for communication, and one of the lawmakers spoken to by Reuters also seemed to favour of an alliance.
"If we can find a common policy platform then I don't see why we shouldn't give them our support," said Sebastiano Barbanti, the Calabrian deputy.