Shortly after World War II, the first deluxe Shas published in America appeared on the market. R’ Moshe Feinstein zt”l purchased one as soon as it became available. He would learn from one of these volumes at his desk in the beis midrash of Tifereth Jerusalem, where he also kept a bottle of ink, fountain pen and paper to record his chiddushei Torah. One day, he left his desk briefly and while he was out, one of his talmidim accidentally tipped over the ink bottle on the new Shas gemara.
The boy felt terribly embarrassed and he and his friends stood around nervously as they waited for R’ Moshe to return. Seeing what happened, R’ Moshe broke into a pleasant smile and said that blue was his favorite color, and the gemara looked even more beautiful than before. He sat down and returned to his writing as if nothing had happened. ~ 5 Great Lives