The SHTF scenario I'm waiting for wasn't one of the choices listed.  It's the day when Hell has no more room and the dead walk the earth. Yup, Dawn of the Dead.  Need to start working on my SHTF:Undead treehouse retreat.

The chances of anything happening are slim enough that I don't take extensive precautions (i.e. stockpiling mags and water and food and gas masks and ammo and spare identities).  If something DID happen, I wouldn't be able to take all that with me anyway (plus, I can't afford all that fancy stuff at this point in my life).  However, the scenario I picture would be a result of massive attacks on our country (Nuclear, Biological, whatever).  

In the last 100 years TSHTF how many times?

WWI & WW2 certainly stand out.

The Russians killed millions of their own people.

Pol Pot killed hundreds of thousands in SE Asia.

Mogandishu was a thriving sea port in the 80's but turned into the real world version of the road warrior in the 90's.

Serijevo hosted the winter Olympics, then a few short years later had a complete collaspe into civil war/genocide.

But it could never happen here, we're different.

I've said it before and I'll say it again, too many people compare WTSHTF and TEOTWAWKI.  TSHsTF every day somewhere.  Ice storm knoks out your power for more than a few days?  Evacuated for a hurricane?  Riots (not just LA, Tampa has had a few also)?  If you are home during a burglary, TS has HTF for you (and hopefully mr. Burgler) even though the rest of your neighborhood lies in the blissful arms of sleep.  

Mad Max is TEOTWAWKI.  Several nukes on continental US is TEOTWAWKI.  I doubt (and hope we don't) we'll see that.  Everyone is going to see TSHTF.  I've been through it twice.