Loaded up GTL to list some stuff, saw a $1,000 ditto. Didn't get it in time but wowza.
I've had it happen to me before where I put a pokemon in the sell window, switch to the listings tab to search out comparables, and it will auto-post it for 1k. I learned not to do it after the 3rd time it happened to me. Might be something to do with a scroll wheel on a mouse or a random glitch.
But dayummmm someone is pissed and someone else got a frickin' steal.