I've been reading an unhealthy amount of fanfictions, and virtually ALL of them have been terrible, except one. it's called "Fragile". It's a Sonic fiction, but it's definitely worth a read!
Sonic and Sally have to get the Chaos Emeralds before the good doctor decides to use an awesome machine to take over the world, and Sonic has to discover his feelings for Sally. It's quite easily the best i've read.