Ah sorry I thought you where someone else that had been here longer. lol.
OK
-Make a brush and origin, which is a brush with the
origin texture, and put the origin brush roughly in the center of the other brush.
-Tie them to entity, func_train,
-Name it train1, and set it's target to corner1, set the speed very high,
-Make a path corner, name it corner1,
-Make a env_laser, then set its name to laser1, and its target to the func_train called train1,
-Move the path_corner infront of the scientists head,
-Then if you want it to be triggered make a trigger_once and set its target to laser1, so that when you walk through it, unless you want the scientists head to be blown of beforer the console window has lifted then you will neeed a trigger_once.
Also there are a few usefull tutorials:
http://cariad.co.za/twhl/tutorial.php?id=12 - the laser tutorial,
http://cariad.co.za/twhl/tutorial.php?id=10 - the func_train set up guide,
http://cariad.co.za/twhl/entityinfo.php?ent=env_laser&game=1 -the laser properties.
That should work, happy mapping.