The tickets, put on carelessly parked cars in Potsdam, include a fine of 0 euros and the cheerful message "Glueck gehabt!!!" (Lucky you!!!). The new approach is designed to admonish motorists without hitting them in the wallet.

"The tickets serve as a warning to parking offenders," said Regina Thielemann, a city of Potsdam spokeswoman. "They're issued when the driver isn't around. So they're given written notice when they'd ordinarily only get a verbal warning."

Potsdam, the state capital of Brandenburg just outside Berlin, earned around 1.2 million euros from parking fines in 2011, she said. Around 120,000 parking fines were issued last year.

In Germany -- a country known for its fondness for obeying rules and punishing offenders -- Potsdam's fine-free tickets have caught the attention of the national media.

One recipient, Kathrin Bach, said her initial reaction to finding a note on her windscreen was one of annoyance -- until she read the message.

"I thought 'Oh no - got another ticket'," she told Germany's Bild newspaper. "I've paid loads of parking fines before because there are so few parking spaces in the area," she added.

Bach's offence -- parking less than five metres away from a road junction -- should have cost her 10 euros, according to the city's parking rules.

(Reporting by Alice Baghdjian, editing by Paul Casciato)

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