SOB can mean something that isn’t polite to say, but in the world of CCW it means Small OF Back.  I recently carried an SP101 this way.  It is one of the best ways to conceal no matter what your attire is for the day.

SOB carry can be done with an expensive holster from Galco or other makers, but you just as easily carry with a very inexpensive Inside the Waist Band holster from Unlce Mikes.  These neoprene type holsters can be found all over the place in the $10-$15 range.  They offer a great platform for this type of carry.

One thing to remember; when you buy for SOB using and IWB holster, make sure you buy it for the opposite of your dominate hand.  A right-handed person needs a left-handed IWB holster for SOB carry.  This puts the butt of pistol pointing to the right, allowing for a very easy draw.

It takes a little getting use to, especially when sitting, but it is actually quite comfortable and very concealable.  The only disadvantage that I see to this type of carry is the small loss of draw speed when compared to strong side hip carry.  However, with a little practice you can become very quick and make up some of that time.