Thanks for your replies.
My organization workflow is similar to yours : I import my photos, review them, delete the bad shots and flag / color tag for selection. Then I edit some of the photos and export them to share on the web.
But what I export is usually not staying long on my disk as I usually resize pictures to share on the web. So I have many edited shots that I can only see (edited) in Lightroom. And since I'd like to mix edited / not edited photos to be able to view them from my hd I guess I have some big exports to do.
That's why I was wondering how other users were organizing themselves... Exporting everything or keeping edited photos in Lightroom ? Deleting originals after edition or keeping them ? Sorry if I seem unclear.
I think I'll just export at a lower resolution to keep "final versions" of my photos that I can easily access and i'll keep all Lightroom collections and originals so I can make changes later if I need or export some photos in higher resolution, etc.