Thumbnailer for directories

[David nolden]

Hi! I'd first like to know if some code for this already exists, else I'd like 
to implement it(Unless it proves to be too much work).

Dolphin/konqueror/whatever should show some of the thumbnails of items within 
the directory as thumbnail for the directory. This is one of the core features 
my mother(an Artist) is missing under linux.

Has any work in this direction happened already, or can someone give me a hint 
where to look to get a fast start?

Greetings, David