In the last company I worked at, we used to refer to each other in memos using our initials - three letters where people had a middle name (most of them) or two if they didn't. Out of only about 30 employees, over the 14 years I was there, there were often clashes.

Perhaps this reflects a lack of diversity in ethnicity, with most of us having Anglo-Saxon names. There was also a high proportion of older employees, from a time when parents didn't choose from as wide a range of names as they do now.