The De Broglie-Bohm theory is a very interesting interpretation of quantum mechanics. The highlights of the theory are:

1. The wavefunction is treated as being real (just as in MWI - in fact the theory is compatible with MWI in some ways),
2. Particles are also real, and are guided deterministically by the wavefunction. In other words, it is a hidden variable theory.

At first it might seem to be a cop-out to assume the reality of both the wavefunction and of actual point particles. However, this leads to some very interesting conclusions. For example, you don't have to assume wavefunction collapse (as per Copenhagen) but at the same time, a single preferred Universe exists (the Universe given by the configuration of the point particles). But that's not all.

It very neatly explains double-slit diffraction and Bell's experiments in a purely deterministic way using hidden variables (it is thus necessarily a non-local theory). It also explains the Born probabilities (the one thing that is missing from pure MWI; Elezier has alluded to this).

Among other things, De Broglie-Bohm theory allows quantum computers but doesn't allow quantum immortality - in this theory if you shoot yourself in the head you really will die. You won't suddenly be yanked into an alternate Universe.

The reason I'm mentioning it is because of experiments done by Yves Couder's group (http://math.mit.edu/~bush/?page_id=484) who have managed to build a crude and approximate physical system that incidentally illustrates some of the properties of De Broglie-Bohm theory. They use oil droplets that generate waves and the resulting waves guide the droplets. Most importantly, the droplets have 'path memory', so if a droplet is directed towards a double slit, it can 'interfere' with itself and produce nice double-slit diffraction fringes. One of their experiments that was just in the news recently illustrated particle behavior very similar to what the Schrodinger equation predicts: http://math.mit.edu/~bush/?p=2679

Now, De Broglie-Bohm theory does not seem to be one of the more popular interpretations of QM, because of its non-locality (this doesn't produce causal paradoxes like the Grandfather paradox, though, despite what some might say). However, in my opinion this is very unfair. Locality is just a relic from classical physics. I haven't seen a single good argument why the eventual theory of everything should be local.