This is very cool: a live camera pointed at the Iceland volcano Eyjafjallajökull. I don't think it's embeddable, so just click that link and take a look. To add to the coolness factor, there is also a thermal camera pointed at it with the same field of view and scale, so you can compare what you're seeing visually with what's going on in the far infrared.
Here's a still I grabbed last night; You can clearly see the ash plume through the cloud layers:
They provide a map of the camera location, but there's no scale. I put it into Google maps, and it appears to be just a few kilometers from the volcano. That matches the rate the plume appears to change, too.
Take a look. It's mesmerizing. And don't forget that the NASA Earth Observatory is posting very high-resolution and beautiful images of the volcano quite often as well. Put that in your RSS feed reader! I check it every day; besides the volcano they frequently have incredible imagery of places I've never even heard of. It's a big planet, with lots to see.