Collaborative stories can be fun but, sometimes they can be a pain. There have to be ground rules and unless you want a grand mess on your hands, a consensus on setting, characters, and just how far you can go.

I was the trail boss for a collaborative story some years ago called Collision. It still out there somewhere. CRVBoy's I think. It was fun to do and it turned out to be a good read.

While I NEVER want to be trail boss again, it could be fun to collaborate. It all depends on the genre, what you like to write and how it's organized.

See if this gets you interested:

The Mobaye Strain

 

Classified CDC/Homeland Security Lab
Forty miles North of Cedar City, Utah

 

The outbreak in the Congo was typical of central African outbreaks. A hemorrhagic fever creeps out of the jungle, wipes out a few villages and then burns itself out.
It had happened before and, it would happen again.
This one was different. Most outbreaks left survivors. This one did not. That's why this little monster had landed in Dr. Andrew McAlister's BL-4 lab.
It was assumed that it was just another jungle bug that emerged from time to time. McAlister was absolutely sure this was not the case. The more he looked at the little bastard's RNA, the more he was sure of it.
It took him, and a few dozen graduate students, a couple of weeks  to figure it out and when he did, the terrifying truth of it was chilling.
Mobaye was a chimera. Thirty-three percent of the RNA was an H1N1 flu variant. Forty-four percent of the RNA was India-66, a particularly nasty variant of smallpox. The other 23 percent was unidentified but, this little bastard of a virus was in no way natural. It had been engineered. The outbreak in an area famous for outbreaks of absolutely hideous hemorrhagic fever could only mean one thing: someone had taken this bug out for a test drive.
McAlister picked up his phone and a ring later the Lab Director answered, "Andy. Have you got some answers about Mobaye?"
"Yeah boss. I'm pretty sure, you are not going to like it. Mobaye was engineered and, it sure looks like someone was testing it."