Faking tilt-shift photos might not be as fun as getting a lensbaby and doing it through the lens, but its easier, and gives a little more control over the final output. The basic principle is straightforward, tilt and shift the focal plane to produce a very sharp dof, not parallel to the camera.

The process is really very simple in photoshop CS and above.

1. Boost the contrast and saturation with your favorite method a little.
2. Start the Quick mask tool, and use the Gradient tool to make the mask. The reflected gradient option that looks like a cylinder works best. Draw a perpendicular line from the area you want in focus, away to the edge of the photo.
3. Exit Quick mask, and apply a Filter > Blur > Lens Blur.
4. Deselect, then apply finishing touches to the saturation until it has the right look.

WARNING: The process can get addicting!

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