I mostly just continue to be boggled by how formal most languages are. I start almost all my work e-mails (I haven't written a letter in years) with "Hi First Name," regardless of how well I know them. I once had to spend several days convincing my German boss that "Hi" is acceptable and that most Swedes would either laugh their asses off, be offended, or assume that it was poorly translated spam if they were addressed as "Highly Esteemed Mr Doctor Last Name."