European Union summits are generally regarded as the place where hard leaders take hard decisions. But Europe's most powerful men - and occasionally women - are not always as serious as they'd like to appear. And their methods can at times be downright childish.
Germany's corpulent former chancellor Helmut Kohl would famously put an end to dreary discussions by thundering: "Ich bin hungrig!" (I am hungry!).
And Silvio Berlusconi, Italy's maverick media baron-turned-politician, raised plenty of eyebrows at the December 2003 summit when he told his colleagues he'd much rather talk about "football and women".
Most leaders, however, have tended to opt for slightly more subtle ways of showing their annoyance.
Jacques Chirac, France's equally mighty former president, would signal his impatience by diverting his attention towards Asian porcelain catalogues while enjoying a few biscuits and mints, recalls Chris Patten, a former British EU commissioner, in his memoirs.
Another former German chancellor, Gerhard Schroeder, would drop heavy hints at his dreary colleagues by stepping out to smoke a big, fat Cuban cigar.
Summits are nonetheless important gatherings affecting the future of millions of ordinary Europeans.
And though most of their conclusions are prepared weeks - or even months - in advance by grey-suited civil servants, they seldom lack surprises.
As one veteran EU observer notes, leaders "don't just come to cross the 't's, there are hard decisions to be made".
Yet personal vanity sometimes intervenes to hijack the official agenda.
At his first summit as French president last June, Nicolas Sarkozy tried to steal the limelight from German Chancellor Angela Merkel by taking the paparazzis for a jog.
And confrontations can occasionally be taken very personally, such as when Belgian Prime Minister Guy Verhofstadt became very emotional after his bid to become president of the EU executive was vetoed.
Though not many prime ministers like to indulge in late night poker-playing tactics, these cannot always be avoided.
By far the most notorious marathon meeting in recent memory took place in Brussels in June 2007, when 26 countries were held hostage for a night by Polish intransigence over voting rights to be contained in a new treaty.
Bizarrely, President Lech Kaczynski would regularly leave the negotiating table to consult his twin brother, then Poland's prime minister, who had stayed behind in Warsaw.
The impasse was only resolved when Sarkozy, outgoing British Prime Minister Tony Blair and Luxembourg's Premier Jean-Claude Juncker won Jaroslaw Kaczynski over in a joint telephone appeal.
Generally, summits run the smoothest when the big three member states - Germany, France and Britain - all agree on a big issue.
That does not always go down well with some of the smaller EU countries, which insist decisions should be made collectively, rather than in Berlin, Paris or London.
"The biggest difference between big and small countries is that the big countries haven't yet realised that they too are small," says one veteran diplomat.
And it is generally agreed in Brussels that the biggest culprits on this front are France and Britain - perhaps because they believe that having a permanent seat in the United Nations' Security Council still gives them enough clout.
Predictably, most of the talking, which takes place during summits, is done by the leaders of the largest countries.
"In Brussels, size really does matter," one expert, notes.
It is usually up to the rotating presidency of the EU, which chairs such meetings, to keep discussions at a minimum and allow leaders to go back to their families at a reasonable hour.
"If all 27 leaders want to talk on any particular issue, it takes at least three hours!" one diplomat complains.
Occasionally, leaders prefer to send their civil servants away in order to have a more intimate chat.
But this is not always relished.
During the 1991 Maastricht summit, then British premier John Major reportedly hid his ambassador John Kerr under the desk because he was terrified that he would accidentally give something away.
And since the spread of the mobile phone, leaders have taken to text-messaging their assistants, a technique pioneered by - who else? - the Finns.
And what do you do when you have a particularly tough nut to crack?
With Chirac it was easy: "You'd just wait for him to have finished his third Corona beer before pressing your point," one insider recalled.