Where to start.
Becky Bain--"Timeless"--it's an Xover, but one of the few I've ever liked; "Ad Astra Per Aspera" is really hard to deal subject-wise with but very well done
Margaret Brignell--"The One" or her whole Only You series
Kathy Brown--"The One That Got Away"--She has others but I think this one is my favourite
Demi--"Heaven's Prisoners"--I think of that one as a baseline for the angst-factor
Jennifer Eagan-Dixon--"When Magnolias Bloom"--this one is kind of bittersweet but was one of the first stories I ever read and I still like it
Sheila Harper--"In the Beginning"--I still love that story
Pam Jernigan--"President Kent"--it's a hilarious take on the idea
Erin Klinger "HiM: the Video"
Lyds--"The Darkness Within"--very alternate reality
BB Medos "Lois' Revenge/Clark's Response"
Debby Stark "Shortest L&C Story Ever"--it's funny and her list used to be my favourite email to receive
Karen Ward--"Nightmare on Hyperion Avenue"
Zoomway--"Counter Clark-wise"--I think it was one of the earlier attempts to mess with alternate realities
You'll notice I left out many authors--including some authors that are regularly included in all recommended reading lists. I even left out some of my all-time favourite stories because they are more recent. I purposely picked the older stories (before 1999). The only ones that deviate from this are those that I know were finished earlier but not uploaded to the Archive right away.
I left the Gorn off the list because none of her stuff is accessible through the main archive. She remains a favourite, though, and her work has been around forever. There are a couple other authors whose work I know I liked but who have since disappeared completely.
