I saw this article a couple weeks back in Scientific American. If you have $28,000 lying around, you can buy a "quantum eraser," which will show proof that quantum entanglement is an actual thing (Einstein was leery of the concept, and called it "spooky action at a distance"). According to the article, the device
...produced pairs of particles that acted like magic coins: when flipped in unison on opposite sides of the lab, both coins always came up with the same side, either heads or tails. Aspect's apparatus produced about 100 spooky coincidences per second. The qutools kit, which would fit on a living room end table, sees more than 10 times as many.
What Einstein found spooky is that there's no way for the particles to communicate with each other, as the effect is simultaneous, whereas information can only travel at the speed of light. The only way for it to work is that the particles, even though physically separate, are entangled in some way that science doesn't entirely understand. We can prove quantum entanglement exists - from your living room coffee table, no less, thanks to the folks at Qutools - but don't yet fully understand the mechanism at work.