Weekend video galore. (Have you seen the video Quince took of Reactor 2?)
This one was taken by carbon-based TEPCO employees as they surveyed Reactor 1 (Isolation Condenser, in particular). The video was taken on October 18, and uploaded to TEPCO's "Photos for Press" page on October 21.
The workers spent most of the time on the 4th floor, surveying the integrity of the pipes for the Isolation Condenser. You do get to see the 3rd and 2nd floors toward the end of the video. One worker calls out the radiation numbers periodically. The highest number I heard was "189" on the 2nd floor.
You can see the light coming in from outside on the 4th floor, giving a warm orange glow to the scene of utter destruction on the 4th floor:
You can download the video at TEPCO, here. Or view it here.
(UPDATE: For this effort, the workers (TEPCO employees) got as much as 9.44 millisieverts external radiation exposure, according to Mainichi Shinbun Japanese.)