The 2N3904 is an old friend who has never changed. I've been using him since the 80s and he's still my first choice whenever anything general-purposey comes along.
BC547? 337? I think they are Texas devices, much popular too.
This is an interesting article on how open licensing can help ensure viability long after the original designer has left the game.
BC109 for ever!
Maybe in US. We had BC107-BC109 and BC177-BC179
Just so long as we remember to check it'll fit the need. I recently inherited a design that used some parts from the 70s and they were not up to the task. Drop-out voltages too high, gate threshold voltages too high; whatever spec could be violated was. Just because it's been used for 50 years doesn't mean it's the right part for the job