Opposite Erich hangs a picture of Walter Ulbricht, the man who built the Wall. There are red flags, with wheat sheaves, hammers and compasses - the emblem of the former German Democratic Republic (GDR). Above the exit, a notice warns: "State Border - Bathing Forbidden". And there is even a statuette of Felix Dzerzhinsky, the renegade Pole who founded the Cheka, fore-runner to the KGB.
All very funny, except this is no joke. "We have no intention of caricaturing the GDR," says the deadly earnest barman, Matthias Ulrich. "This is a business concept. People come here to have a good time."
Die Tagung - the name of East German party conferences in the days when all life revolved around the party - is one of a string of pubs where clients pay to relive the halcyon days of communism. Within limits. "We only play GDR pop at chucking out time," Mr Ulrich says. "Sometimes, when people get drunk, they sing `The Internationale' and other revolutionary songs. It's very moving."
And sometimes, people from West Berlin arrive and try to re-educate their under-privileged Eastern brethren. "They come and start a discussion," Mr Ulrich says. "The problem is, they don't understand the GDR."
But he and the regulars do. Dental technician Rica Gopfert, 24, says: "In the old days, people had a sense of community. There used to be house parties and every resident was there." Things are not like that any more. "Perhaps it's because of capitalism."
This communal spirit is alive at Die Tagung, a former butcher's shop. Everything on the walls was donated by regulars back in 1992 when most people were burning this kind of stuff and trying to forget their communist past. The whole street got together to create this shrine to an out-of- fashion ideology.
But Erich, Lenin and their cohorts are trendy again. The fad even has a name: "Ostalgie" - a play on the words for "east" and "nostalgia". A hard core will bop to old East German rock, and on special nights, such as May Day, will dress up in a young pioneers' outfit, red scarves and all.
They sip Berliner, one of the truly great brews even by German standards, but a beer that evidently does not travel well. At least you cannot find it in West Berlin, which is flooded with inferior products. They sit there and reminisce about happier times, when rents were lower, unemployment was the disease of the decadent West, and everyone was equally poor.
"There was no job competition in the GDR, and the wage gap was narrower," says Mr Essebier, a 35-year old customer who has been coming to Die Tagung for years. "You didn't have these privileged people who earn many times more than the masses." Today, it is all greed, aggression, and it gets on his nerves. Like most of his compatriots, he speaks from personal grievance. He is a qualified history teacher, but could only get a job in a children's home. History was re-written just as he came out of university.
On Fridays and Saturdays, Die Tagung is packed. The "business concept" is proving to be a great success, but the owner has enough commercial sense to hedge his bets against changing fashions: he also runs the Foster's bar next door.