I tried this once about a year ago with dismally sad results.
I think the secret is finding a decent wide angle shot with lots of items in it that we inherently know the size of.
Then, when the "look" of having used a tilt/shift lens or a lens with a bellows becomes apparent.
It makes the scene look like a toy world.
I've always liked seeing other's photos done this way, and last night I scoured my archives for images that would possible show the effect as I envisioned it.
These were the only two out of about ten that even looked half-way like I wanted.
I'll have to keep an eye out in the future for scenes that would lend themselves to the tilt/shift lens effect in Photoshop Elements.