This is not necessarily my cup of tea as an iPad stand (the angle is not adjustable), but I find the technology behind the stickum fascinating.

Slope is an elegant, minimal tabletop stand that gets your tablet upright and out in front of you with an easy in/out attachment. It works by way of a unique suction technology, mimicking the specialized toe pads common to the Gecko lizard. The foam of the two pads grip the flat surfaces of both table and tablet with microscopic suction to give a firm mounting experience and solid feel. The pads are extremely durable and replaceable.

Dust and dirt have got to be the big bugaboos here. Interesting idea.

[Hat tip to Mike Russell]