Prequel Adventure (aka Making a Cat Cry: The Adventure) is pretty great. Took me a good two months to finish the thing, but it's not done yet. We (the readers) have been waiting for an update since October 31st, 2015. I think it might be an Elder Scrolls IV: Oblivion fan fiction, but the main character's a Khajiit, so it's kinda furry? I think? It gets kinda weird at times. There's even mini games and animations added into it (only accessible on computers), not including the gifs that make up the comic.
Another great one is Sabrina Online. Read that in a day, beautiful story.
I wanna make my own web comic, but I can't draw to save my own life!