what are your views on these?
i'd say that in general they are a waste of time, a chance to throw out some half baked idea or jam that would be far better if it had stayed off the record.
i have nothing in particular against untitled extra songs that appear after the other tracks, and can think of a few i like a lot. theres no real reason for them to be 'hidden' though, unless they are completely out of step with the rest of the album, in which case they can fuck off.
but the ones that really piss me off are when the final track is about half an hour long, with 20 minutes of that being silence. i can't think of a single example where it would be worth the wait to get that last 30 seconds of meh, but i can think of many where the 'hidden' section is a pointless exercise that makes it more difficult for me to enjoy the album. i'm particularly looking at you Blood Mountain.
so, any examples of necessary 'hidden' tracks to prove me wrong? maybe there's some that have an innovative purpose. though its not quite on topic, i like how on Geogaddi by Boards of Canada the final track 'magic window' is a couple of minutes of complete silence which takes the album length to exactly 66 minutes. which fits in nicely with the spooky mood