A custom, symetrical, double side riveted, "Concealex" sheath compliments my Mean Street.
It has a Tek-Lok that allows multi-position AND location carry i.e. diagonal, vertical, horizontal, any side, upside down, saber grip draw (though I see Bob Kasper's point: see March 2001 "Tactical Knives Magazine" page 38), reverse grip draw, natural grip draw, etc. It can be used for Ankle Carry (with a strap), LBE Carry, Belt Carry, Pack Carry, Suspender Carry, etc.
The TLIQ (Tek Lok In Question) can be removed and replaced with an IWB (Inside the Waist Band) Loop that can be placed anywhere also for multiple carry options.
For those not familiar, let me explain. When you screw on the IWB Loop to the "top o the sheath" you can insert the sheath inside your waist band and wrap the IWB Loop around your belt OWB (Outside the Waist Band), and then snap it back to itself to secure the sheath so that it will not pull out with the knife upon your draw.
Lastly, the double riveted, symetrical sheath has many rivet holes for lashing to anything with paracord, twine, etc.
I am also a BIG FAN of the Kenny Rowe Custom Leather Sheaths Andy Prisco offers. They have some very unique "features" that can secure the blade and sheath very effectively yet still enable quick/easy sheath removal and blade draw. His patterns and tooling are the best custom leather knife sheaths I have seen.
Some folks don't want to spend the money on a custom sheath. "IMHO" and it is "H" I will plunk down the cash for'em in a heartbeat. My reasoning is that if I am going to spend the money on such a quality piece (knife), why not spend the money on a unique, effective, custom sheath, tailored exactly to my specs.
Moreover, if you are going to carry it daily, I like comfort and OPTIONS.
Just my $.02.
Enjoy your Mean Street!