This is just an idea to improve Konqueror. It would store screenshots of the websites you have in the bookmarks so you can see them when you put the mouse over each bookmark. It would also display them in the bookmark editor.
That could be combined with a "bookmarks:/" kioslave that also showed the screenshots.
I don't know how to implement it, but I don't think that would be hard to do.
The screenshots I attach are a fake. They've been made using GIMP.