I'd configured APC to cache content for 24 hours, so luckily I was able to write a small script to fetch all of the content that had been viewed today (still lost previous work, but it's data I hadn't viewed for a while and isn't important).
I once accidentally did the exact same (though my HD was loaded with movies/tv shows/music, etc.). If you spot it fast enough you can recover the data easily with free software.
Yea, sadly enough I was too ignorant to save any data at the time .