I'd seen this coat of arms in my meanderings through Cambridge, but it wasn't until I got home and sat down to research it that I learned anything about what it was or its history.
The arms, found inset into the exterior wall of this building, are those of the Regius Professorship of Civil Law at Cambridge. Purpure a cross moline or on a chief gules a lion passant guardant or charged on the body with the letter L sable. Crest: A bee volant [en arriere] or.
The Regius Professorship of Civil Law is one of the oldest and most prestigious of the professorships at the University of Cambridge. The chair was founded by Henry VIII in 1540 with a stipend of £40 per year, and the holder is still chosen by the Crown. The Regius Professorships are "royal" professorships, being created by the reigning monarch. The first five Regius Professorships (Divinity, Law, Physic, Hebrew, and Greek), sometimes referred to as the Henrician Regius Professors, were established in 1540 in the reign of King Henry VIII (hence the term Henricius Regius Professors), and granted arms and crests in 1590. Other Regius Professorships at Cambridge are those of: History (1724), Botany (1724/2009),* and Engineering (2011).
In any event, with only eight Regius Professorships out of everything else at Cambridge University, I'd say that this coat of arms (along with the arms of the other Regius Professorships) qualifies as some "very special" heraldry.
* The two dates for the Regius Professor of Botany is because the chair of the Professor of Botany at the University of Cambridge was founded by the university in 1724. In 2009 the chair was renamed the Regius Professor of Botany.