I've got some of my own fanfiction. (Yes, it's stupid to promote my own fanfics, yet I need all the reads and reviews I can get!)
Here are some of my more popular ones, as well as one I recommend:
http://www.fanfiction.net/s/8264120/1/Doppelganger - Doppelganger. Kaito catches a cold, and he has to use a doppelganger - Shinichi - to carry out his next heist.
http://www.fanfiction.net/s/8111716/1/Legacy - Legacy. According to Toichi's 'will', he's still alive, and in hiding!
http://www.fanfiction.net/s/8151913/1/bField_b_bGuide_b_to_bDetective_b_bConan_b - Field Guide. A quirky mix of humour and DC descriptions (so far...may be MK characters in future.)
http://www.fanfiction.net/s/8284216/1/Prophecy - Prophecy. Shinichi, Ran and Heiji have been kidnapped! Who's their captor?
14/7- My newest fic. http://www.fanfiction.net/s/8317645/1/Secrets_and_Dreams
http://www.fanfiction.net/s/7844842/1/Of_Fire_And_Water - Of Fire and Water by Nechangi.(KaiShin) A heist brings Kaito and Conan together, and with a little humour and detective stalking, Kaito finds out the truth behind the shrunken detective...
For crossovers:
http://www.fanfiction.net/s/7947232/1/The_Skys_The_Limit - The Sky's the Limit. Maximum Ride x DC. Ai's hiding something, and it will change Conan's life forever...
14/7- The reason I listed these: The general public seems to say that these are the most well typed of the 31 (as of today) fanfics I've published. Each of them are very original too.