I'm reluctant to use Delicious for that because who'd want to see a fic you'd written tagged with "this sucked"?

Delicious has a little ticky box in each entry that says "mark as private." If you check the box, only you can see those bookmarks. It's kind of like flocking a post on LJ--the entry shows up with a little padlock next to it and no one else can see it unless you give them permission.