I have a few fan fictions worth mentioning.
Sonic - Haunted Mansion by Diableos Auros
To start off, I think we all love a murder-mystery, and the new fan fiction by Diableos Auros delivers. Its about Sonic and all his friends and rivals, mixed in together in a big haunted mansion. One-by-one they get killed off... and the killer is inside. The writing skill of the author is high, and his word choice is brilliant. A fantastic read and I hope you all comment and enjoy.
Super Mario Sunshine: Paint of Plague by yoshi007
This fan fiction is based on Super Mario Sunshine, the 2nd 3D adventure by everyone's favourite Italian plumber, Mario. This fan fiction is only its beginning stages and its definitely worth the read. Starting off dark and mysterious, this story definitely has a worthwhile concept and I would suggest it to everyone.
Through the Ages: A Pokemon Journey by LuigiMan & Jordzz
Now, I don't mean to sound up myself, but I think you all should read the new collaboration fic by LuigiMan and myself. No one has ever seriously done a Pokemon fan fiction, so we thought that you all might enjoy one. Written by two experience fanfiction authors, I think that you guys will enjoy the unique concept and storyline that this fan fiction brings you. I hope you all look into it.
Mario and Co: Haunted House by LuigiMan
This fan fiction is definitely one of a kind. The first "haunted house" fan fiction, based upon the uncompleted version by myself, LuigiMan definitely delivers the goods in this completed fan fiction. All your favourite Mario characters are tightly packed away into a haunted house, where one of them inside is the killer. Full of twists and turns, this murder mystery is sure to give you readers a kick. I highly recommend this unbelievable story written by a sensational author.
These are my current fan fiction picks, and I hope you guys look into them. Its all my opinion, though.