The second video episode on Half-Life map secrets. The episode shows in detail how to find hidden rooms, get into various hideouts on the maps and so on.
The episode was ready a long time ago (a week after the first one), but there were problems with it; in particular, instead of the hldm.org intro there was a black screen for a couple of seconds.

Secrets video, episode #2. In this episode you'll see the secrets of the following maps: the_beach, rapidcore, killbox_wood, levels.

https://www.youtube.com/watch?v=OyZhsJTmmA4