For the record, I consider the Oracle tnsnames.ora to be just a file so I feel nothing for it per se. It's just a DNS file for mapping Oracle Server names to IP addresses.
However, mentioning it invokes images of suffering and woe.
With all the Oracle servers my company runs, it's constantly out of date. To make things more exciting, the DBAs don't like the names that we (in development) give the DBs so they insist on giving it there own names. And then for added excitment we have separate DBs running in different countries - each with their own config.
So whenever I have an issue with connecting to a certain DB, I ask the DBAs for the latest settings. And as usual, I get several new conflicting tnsnames.ora entries from the DBAs and/or IT people. The only thing you can guarantee is that most of them won't work. The joy of peer based personal sneaker-net backups.
This problem is easily solvable with some simple source control.
But that will require large quantities of feces hitting a giant spinning blade of doom before that ever happens.
Thus my woe. I'm not a big enough pile of shit to effect change ;-)