Potty Training 2: Electric Boogaloo?

I'm wondering what else to say about potty training, since my own experience is so limited. And I've noticed that the parents I know don't seem as consumed with potty training issues as we are/were with feeding and especially sleep problems, so we don't talk about it constantly. I wonder if there's some shared wisdom that's being lost with our generation because we're just not talking about it as much as past generations were.

One important thing to bring up is that it's often a shorter process to potty-train a child that's "older" when you start, meaning over 2. (Witness P's stomach-churningly daring but successful plan to go cold-turkey, or -Blue's done-in-a-couple-of-weeks system.) OTOH, it seems like a kid who is closer to 3 when you start can be resistant and really dig in her heels. I've been told that there's definitely a window in which kids are interested in potty training, and if you miss that window it'll be much harder to train. My own personal guess is that there are several windows that vary from kid to kid, so you have to be alert and hop on the interest when it pops up.

So here's a question for you guys: If, for whatever reason, you've missed that typical early-2-year-old window, how do you get an older kid (closer to or older than 3) to be interested in training? I've gotten this question several times by email, and the only thing I can offer is to try to use peer pressure and have the child spend as much time as possible with a potty-trained child. But is there something else they can be doing? Surely there's got to be another answer, since you don't see many kids who are still in diapers at the age of 4.