When I met my husband he already had one friend named Julia, so for quite a while I was “other Julia” among his friends. I have now graduated to being “Julia” rather than “other Julia” in many areas of my life, but some of my circles have better-known Julias.
It seems to me this is a benefit of rarer names. Jeff and I have fallen into the bad habit of identifying our friends by things like “actuary Ben”, “Harvard Ben” and “mustache Ben”, although we have finally started using the surname of this last one since he lost his mustache.
Getting a unique combination of first and last name is a different problem. This site lets you find out how many people there are with your exact name. The methods seem to be having a very unusual first or last name, or combining a first name from one ethnic group with a last name from another. I’m not too keen on any of those options.
When we have kids, we’ll probably aim for first names that are fairly unpopular without being too bizarre.