From ethnic Albanians in southern Serbia to the Serbs of Republika Srpska, separatist leaders are asking the same question in the wake of the banned Catalan referendum: Why don't we do the same?
On election day, graffiti of Catalan flags appeared in Novi Sad and several other towns in the northern Serbian province of Vojvodina, along with the claim that "Vojvodina = Catalonia".
Meanwhile in the southern Bosnian town of Mostar, a giant banner appeared near the cathedral showing the flags of Catalonia and Herceg-Bosna, the self-styled Croat entity, reading: "Good luck. We are the next", according to local media.
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The fact that one region - Kosovo - managed to secure its independence has emboldened many like-minded leaders in the region, while infuriating many others.
Brussels's argument that it considers Catalonia's referendum illegal, while backing Kosovo's independence as a "special case", infuriated Serbia, which denounced the EU's "double standard".
'How did you legalise?'
Belgrade has fiercely rejected Kosovo's unilateral declaration of secession in 2008, which carved off the southern Serbian province into a country in which 90 percent are ethnic Albanians
The move came a decade after the bloody 1998-1999 war which claimed 13,000 lives, ending only after an 11-week NATO bombing campaign which kicked Serbian armed forces, controlled by Slobodan Milosevic, out of the breakaway territory.
"How did you legalise the secession of Kosovo even without a referendum?" Serbian President Aleksandar Vucic asked.
"How did 22 EU member states legalise the secession that violated European law which is a foundation of EU politics?"
Mr Vucic, who at the time advocated a "Greater Serbia" as Milosevic's information minister, has firmly backed Madrid as he now faces the possibility of resurgent nationalist fever at home.
Among the potential hot spots are the southern Presevo Valley - another home of ethnic Albanians, the Muslim-populated Sandzak area, and the autonomous province of Vojvodina with more than two-dozen minorities.
Nenad Canak, the leader of the regional LSV party and a staunch advocate of Vojovodina's self-rule, went to Barcelona for its October 1 referendum.
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But for Florian Bieber, a professor of southeast European studies at the University of Graz in Austria, Vojvodina is not a cause for worry.
It is a region "with some sense of identity, but no strong movements for independence and no cultural distinction of the intensity in Catalonia", Mr Bieber told AFP.
But that is not the case with the Presevo Valley bordering Kosovo and its 75,000 inhabitants, most ethnic Albanians who fought against Serbian forces in 2001, hoping to throw off Belgrade's rule and join Kosovo.
The conflict ended with an internationally brokered peace agreement.
Jonuz Musliu, the hardline leader of a region's ethnic Albanian party, seized the Catalan referendum as a chance to urge global leaders to recognise the 1992 ethnic Albanian referendum in southern Serbia, which has largely been ignored.
"A referendum about ethnic Albanians in the Presevo Valley is also legitimate," Mr Musliu said.
'Real potential case'
Bosnia also has a delicate line to walk with the Republika Srpska, home to Serbs who make up nearly a third of the country's 3.5 million people.
More than 20 years after the war that claimed 100,000 lives, Bosnian Serbs are more turned toward Belgrade than to Sarajevo, and the Republika Srpska president, Milorad Dodik, has repeatedly threatened to organise an independence referendum.
"It may be the time to start talking rationally about a possible peaceful separation in Bosnia," he said after the Catalan vote.
For Mr Bieber, "in the case Catalonia were successful, it would encourage... Dodik to pursue his goal".
Mr Bieber also said he believed there was another "real potential case" that could be inspired by the Catalan vote - Serb-populated northern Kosovo.
In the Serb-run part of Mitrovica, a northern Kosovo town divided along ethnic lines, Serbian flags are everywhere and Vucic's portraits are omnipresent.
This summer Foreign Minister Ivica Dacic openly advocated "a separation, or whatever it is being called" of the northern Kosovo that borders Serbia.
But regardless of the outcome in Catalonia, Mr Bieber said, international leaders will show little appetite for a new and potentially painful redrawing of Balkan maps along separatist lines.
The international community recognises new states "in extraordinary circumstances" such as a "massive repression... a strong, violent independence movement, as in Kosovo... (or) when the state had already disintegrated... as it was in Yugoslavia," he said.
"Catalonia does not fit any of these categories, and neither Republika Srpska nor the north of Kosovo would qualify."
