Stuart Weibel talks about that old nugget, the globally unique persistent identifier.
In Kripke-speak, this is a rigid designator.
It is very appealing to embue rigid designators with semantics. Sometimes by making them proper nouns. Sometimes by making them intensional.
The hard problem is finding any semantic that is rigid through time and in all possible contexts. Hence the magnetic pull towards opaque identifiers such as numbers.
The Web is a wonderful example of what happens when you let everyone loose to create their own identification schemes. Identifiers are social constructs. The problem of identification is ultimately a problem of language.
Human language is surface chaos with a consistent underlying form. As byproducts of language, we should not be surprised that identifer systems are similarly chaotic on the surface.
Utterances are always a rich steamy broth of the extensional and the contextual. The context bit is what makes us human. We take short-cuts in utterances all the time. That is the context.
Obviously, this drives computers mad because computers don't do context.
It also drives non-computing folk mad because they cannot see why the heck the computer cannot just use the context like everyone else.
Computing is a fun field :-)