Amazing (and Scary) Japan Tsunami Video and Photos
These three videos have compiled a large amount of the amazing video footage into a few YouTube videos, In Focus has a pile of amazing photos spread among two articles, and The Big Picture does as well.
Update: Related, if you're concerned about the damage to the nuclear plans and if they could cause more trouble, this Reddit AMA with a former nuclear emergency planner (and current nuclear engineer) will clear things up and put to rest some of the "Holy cow, the world's going to be covered with radiation!!!!1111leleven!!11!" concerns.
And I just came across this video that was pretty intense and this video (direct download -- right-click, save as if it doesn't work in your browser) that was downright frightening (I think both of these clips are part of the above links, but not 100% sure).
Update on 3/14: These before/after satellite photos are absolutely amazing and terrifyingly frightening.