I think Craft is Greece's only microbrewery. Its excellent beers are on sale in various bars in the city and elsewhere in Greece. The bar/restaurant on Alexendras Ave also houses a brewery and serves beer-friendly grub.
The smoked lager is particularly unusual and goes well with the sausage platter. Red Ale, Black Lager and Weiss beer also tasty.
205 Alexandras Avenue
Tel: +30 210 646 2350
www.craft.gr/
Nearest station: Ampelokipoi
Updates
Craft isn't the oly microbrewery in Greece! Excellent one here in Messinia started 2009. Beer originally called Messina, problem with the name, so now marketed as Neda. Only local limited availability at the moment but I hope that will soon change!
Is this your business?