This user is an MathOverFlow representative of the Lviv Scottish Book, a book with open mathematical problems inscribed by visitors of the famous Scottish Cafe in Lviv (Ukraine).
The Lviv Scottish Book continues traditions of the famous "Scottish Book" (1935-1941) containing open problems posed by representatives of Lwow Mathematical School (S.Banach, S.Mazur, W.Orlicz, J.Schauder, H.Steinhaus, S.Ulam and others) of interwar period.
Usually, mathematicians writing problems to Lviv Scottish Book suggest some prize (a bottle of wine, a dinner in "Szkocka", etc.) for solutions.