I've seen several people link to the Scientific American piece on how to make your own "quantum eraser" experiment, which also includes a list of components and a detailed set of instructions, with pictures. There's a great "living in the future" kick to an article which assumes that you just have a laser lying around the house, and the basic demo is pretty cool.
The one quibble I have with this is that I think it's a bit of a stretch to call this a "quantum eraser."
The basic scheme here is that you take a laser, and diffract it off a small solid object taped between two perpendicular polarizers. Light that passes to the left of the object thus ends up horizontally polarized, say, while light passing on the right is vertically polarized.
If you looked at the diffracted light without the polarizers, you'd see interference fringes, but with the polarizers in place, there's no interference. If you take a third polarizer, though, and put it in the beam after the first two, you find that the fringes come back when you orient it at 45 degrees to the first two.
You can interpret this as a classic "quantum eraser" experiment, with the pattern being destroyed because there is path information encoded into the polarization of the photons. When you put in a 45 degree polarizer, it's equally likely to pass either polarization, so you've lost the ability to distinguish between light that took the left-hand path and light that took the right-hand path, and you recover the interference pattern.
The problem here is that this can also be explained perfectly well using classical fields. You get no interference when the polarizers are in place because electric and magnetic fields are vectors, and orthogonal polarizations won't interfere with one another. You recover the pattern when you put the third polarizer in because it's equally likely to pass either polarization, and on the far side, the fields have the same direction. This shouldn't be a surprising result to anyone who knows Malus's Law and the wave model of light.
For this to really be a quantum effect, you need to do it with single photons. It's really only unequivocally a quantum phenomenon when you have a single particle in the apparatus, and it still takes both paths around an obstacle. Of course, that's kind of hard to see...
This is, as I said, a quibble. The apparatus they describe is very clever, and the effect is pretty cool (I particularly like the trick where the split the analyzing polarizerso you can see the shift in the fringes for the two different 45 degree orientations). I may put together a version of it for later this term, and I'll definitely print the article out for future reference (some of my Quantum Optics students gave presentations on the quantum eraser, and it'd make a great demo for an oral report). It is, however, a quantum eraser only in a lies-to-children sense, and is not by itself sufficient to show the weird quantum nature of light.
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Look. Quantum "eraser" means follow U with a U^{dagger} before anything goes click. Yawn! This experiment does point out that making a measurement between two others can make a difference in the final result. And that things don't commute. 45 guy inbetween two crossed polarizers is different than crossed polarizers followed by a 45. So it hings at quantum. But rotations in 3d don't commute either; rotate a book along the z axis by 90, rotate it around x by 90. Then take anohter book and do those in the opposite order, you get different results.
To do real quantum stuff its neccessary to do it with a single photon as you say, but polarization is quite robust, that is why quantum key distribution/cryptography is well beyond quantum computing IMHO.