Thumbnails for .FLV files ?

[smallworld]

I have a massive folder stuffed with gigs of .flv files that I have got from tinypic and youtube etc.. All files have obscure and meaningless names. I cannot enable windows XP to display the folder contents as thumbnails. Anybody have any ideas how I can create thumbs for flv's without converting them all to another format. Maybe there is a media organising program that you have heard of ? Thanks in advance. My file associations seem ok, and I already have several programs to just play the files.