Potatos Flashing Light
That's a bug in Hammer. Go to ThePortalWiki's page of GLaDOS voice lines, find one you like, and mouse over the Download link to see the filename. The scene name will be almost the same as that.
So I have to download the line I want and put it in Hammer? Then I pakrat it into the file for sharing?
EDIT: Or are you saying I can preview them from there? Well, that's helpful, but Hammer won't either let me preview the sounds, nor will it play them in-game. At least Potatos wouldn't play ingame.
EDIT: I just tried a normal GLaDOS line and it played. The extremely freaky part was that I had a Potatos gun and her light WAS STILL SYNCHED to GLaDOS.
EDIT: Just tried a Potato line and it worked. I guess some of her lines are broken, then.
Anyways, thanks for the help. 