Fantasizing about what it would like to have already finished my Great American Novel/Web Site/Open Source App gives me such a warm and comfortable glow that I am reluctant to spoil it by taking two steps into the project and looking around and saying "OMG this is total crap and I have no idea what to do next".
PS: And yeah, the pomodoro method rocks.
I find myself procrastinating at work because what I do for work isn't intellectually engaging, and with tasks that I want to work on for myself (like building my web site) I get hung up on details and make no progress.
Learning to set smaller milestones has helped with the latter, but the former is something I'm stuck with for the moment. My web site is a step to escaping from that grind, but it's going to take time... so I'm taking advantage of the fact that my job isn't sufficiently challenging to require much thought, and therefore saving my energy for things that actually matter, which is everything else. :)
I've since learned that I have to force myself to accept the "good enough" solution, to work in iterations, and to do timeboxing (I use the pomodoro method) so that I just get started on something, without worrying too much about the big picture. Most of all though, it really does come down to just mental discipline, to recognizing when you're putting something off (which itself can be difficult to a life-long procrastinator) and forcing yourself to just do it now. Sadly, like a recovering drug addict, I'm afraid it's something I'll always have to fight against.