One of the things I like about the internet is that it allows authors to show people things that never made it into the final drafts of books. A lot of times, there are good reasons for not including these scenes (like, they suck?), but it's interesting to see them nonetheless. It's like the extras on a DVD - you can look at those extras without polluting the author's final version of the text.
In the book that I'm working on now, there are a LOT of those extras. This book has gone through several incarnations over the years. There was a version in which there were four sections, each of which was told from the point of view of another character. It was a disaster. Interesting (at least to me), but seriously a disaster from a book perspective.
Also, when I started writing, I wrote a lot of scenes that I wanted to see that didn't actually fit in anywhere once the plot finally crystalized. That blows, because I really like a lot of those scenes. They're cute. They're funny. They have good banter. They're sexy. At least some of them are those things. To me. :) But they don't work, so they gotta go, and any relevant character revelations that happen in them have to be moved into other scenes. It's for the best, of course - it makes the remaining scenes stronger and gives them more depth - but I really liked that scene where my main character S goes to a track meet! It didn't do anything, once I took a second look at it, but it was charming and let me put one of my guy characters in those short track shorts, which was fun.
Even in the latest incarnation of the book, I've had to get rid of a couple of scenes that I really liked. It's because of the way I write - I just go where the idea takes me and see what happens, so I go down a number of false paths and have to back up to the crossroads and start over. I don't mind; it's just a fact of my writing life.
The challenging part, though, is how to recognize when I'm falling in love with a scene because it's something I wanted to see or because it's cleverly done, and when to recognize that I'm falling in love with a scene because it's doing what it's supposed to be doing (and is cleverly done, of course :) ). Typically, my extraneous scenes involve very little action - that's the twig for me. If the characters are standing around talking about something that's not plot-related, I'm wasting time. Not that the character development shouldn't be shown somewhere else, but it needs to be done in conjunction with forward movement, not separately from it. Assuming I get published (a big assumption, I know, but it's my party and I'll dream if I want to), I'm totally going to do up a website with a whole bunch of scenes and early versions that never made it into the actual book, just in case people are interested.