Raid Ant/Roach Killer does not work on spiders.
It does disorient them enough to make them fall from the wall or ceiling that they happen to be perched on, but if you don't follow through with an immediate squishing, what you then have is one really loopy arachnid staggering about as if tripping on really bad 'shrooms.
And if it's 4:00AM, and you're more than a little arachnophobic, this is a
really bad thing
It all started, as many objectionable things do, on IRC. -- Paul E. (6/10/02)