I too have had the pleasure of watching my rear driveshaft clattering down the road in my rearview mirror. ('75 Blazer 4x4)

After coasting to a stop, walked back, collected my driveshaft, locked the front hubs, and drove around for the next couple of days in 4wd hi (actually front wheel drive high) until I got a chance to replace the yoke and u-joint on my driveshaft. No ill effects to the truck at all.

 

Gotta love these Hill Jack techniques/anecdotes!

When I blew the spider gear through the rear cover of the D70 on my '98, I just grabbed 4HI and kept on truckin"......

 

I've often wondered why, when they make a 2WD truck they don't just make it FWD and do this. You get a 5000% more traction in the winter with the weight on the front wheels vs. the usually empty rear. They do it for cars abd it makes a lot more sense to me in a pickup. I guess the towing / hauling capacity would pretty much go down the toilet though.