I have iPhoto '09 and I'm trying to conserve disk space as much as I can. I haven't really used it all that much except for basic photo edits (cropping, brightening, etc). I keep backups of my photos so its annoying that iPhoto seems to make a copy of everything and places a 4GB library file on my hard disk. I can move that file to my trash but it just makes another file when it imports my photos. There's Picasa, and I like the interface & speed of it, but it also makes me export everything. I want to retain one copy of every photo on my system. I have archived originals on dual layer DVD's, but I keep finding that these apps are making new copies of everything (unless I'm doing something wrong?). I've been seeing images of Pixelmator and it looks pretty good. Does it make copies of photos, or can I make edits and have it save them over the photo already there? I'm trying to reduce general file clutter any way I can.