What is this Ikea component called?

I'm trying to work out what component 110630 and 112996 are called from Ikea furniture. I'm quite impressed with the utility of these devices: they allow you to align items at right-angles in a precision way, with only casual alignment to start with. Really cool pieces of hardware and I want to find out more about them. They're not just used in Ikea, I've seen them in Argos flat-pack furniture too.

So what are they called? Let me know.

In searching for an answer, someone pointed me at the Ikea Hacker blog. Very cool!

Ikea 112996 110630