I slip my rear tires on a daily basis....
 

And it's hilarious! My family insists that some part of my car is scraping on the driveway when I pull in and I thought that too until the second time when I actively noticed the noise coming from the rear. Lately the traction light has been coming on now too. I'm going to replace the VSC/Sport button with a "Driveway mode" button :D

[ame="http://www.youtube.com/watch?v=1SfGmM1sbu0&feature=plcp"]Subaru BRZ torsen LSD in action - YouTube[/ame]

I'd probably be worried about wearing out my rear left tire prematurely if I didn't slip the tires elsewhere anyways.

Mine does the same thing leaving the entrance at work...every time...

Torque-sensing (torsen) diffs do that. If one tire is in the air the diff is essentially open. But if the spinning tire has even a little bit of grip, the diff will lock up and get you moving.

Hmm interesting, I didn't know about that. I don't know if the title of my video shows up but I was aware that it had to do with the Torsen LSD ;)

That's why racers consider clutch type/mechanical differentials vastly superior: they never act as open diffs, even with a wheel in the air.

:word:

But OEMs use sealed viscous units or torsen diffs because their maintenance is nearly the same as an open diff and won't require special oil additives.

And they're not as noisy or problematic at low speeds/parking lots.

No kidding. My tow vehicle is an Ambulance. Those have clutch type LSDs for snow traction. Ever hear a 1-ton LSD in a tight turn? Sounds like someone wailing on the axle with a sledgehammer.

dude my car does that all the time when i reverse in my garage, at first i thought it scraped til i found out it was the tire spinning

Try welded diff :-)

it didnt look like 1 wheel was in the air in this vid, what would cause it to slip like that at such a low speed?

Maybe gravel? Dunno....

Haha did that on my old suzuki samurai, tires chirped around every turn :D

Gravel. No traction under that tire because the surface of the road (gravel) moves as the tire spins.