Kudos to the presenter for structuring the presentation for quick and early audience participation, and for taking on the challenge of writing something in realtime! =) He's doing a quick tic-tac-toe game with the help of some PHP code he prepared before and a framework called PBJ, which isn't linked on the Democamp site and is near-impossible to search for.

Look at that, programming with maybe a hundred people in the
audience catching missing parens and stuff like that. =)

Random Emacs symbol: gnus-article-washing – Group: Special commands on articles.