It depends upon what you want to scan: sizes of objects, and expected
detail.

The Kinect is fundamentally unsuitable for use as a scanner: it is a very,
very noisy sensor, and it has a very low resolution. (time-of-flight is not
good for precision work)

I'm guessing that the most likely use is something in the 1cm to 200cm a
side range, for use in a 3D printer.

The best option with our budget at this point is to make a scanner. Laser
line scanners or structured light are a good way to go, as they are
inexpensive, and can be adjusted to scan objects of different sizes, after
calibration.

There are a good number of builds out there, and it's a fairly
well-documented thing.

In general, you need a good camera, turntable w/ stepper, and either a
laser line or a decent small projector that can be controlled precisely.

Contact probes are very accurate, but they're problematic to use, not to
mention expensive.

This is the Hack Space! Let's build one!