I did a search and found the following
Quiver Scabbard (A&EG, p22,24,25)
Quiver Scabbard: Cleverly designed, this quiver
(for either arrows or bolts) has a hidden scabbard that
can hold a relatively flat weapon of size Small or
smaller, such as a shortsword, handaxe, or dagger. It
increases the Search check DC by +6 to locate a
weapon hidden within.
Weightless Scabbard (A&EG, p138)
Weightless Scabbard: This magical scabbard
grows and shrinks in size to accommodate any Large
to Tiny bladed weapon. This includes greatsword, falchion,
scimitar, rapier, longsword, short sword, and
dagger. While the weapon is in the scabbard, its
weight is reduced to zero, although the scabbard
retains its own weight.
Caster Level: 3rd; Prerequisites: Craft Wondrous Item,
reduce; Market Price: 1,600 gp; Weight: 1 lb.
Sacred Scabbard (MIC, p183)
SACRED SCABBARD
Price (Item Level): 4,400 gp (9th)
Body Slot: —
Caster Level: 4th
Aura: Faint; (DC 17) transmutation
Activation: Swift (command)
Weight: 1 lb.
This hardened leather scabbard is
inscribed with pictograms depicting
many different kinds of weapons.
A sacred scabbard can change
shape to fit any dagger, sword,
or axe touched to it, even
making allowances for
double weapons. The scab
bard keeps any weapon
carried in it clean and
sharp. Furthermore, three
times per day, you can
command it to produce a bless weapon
effect on the weapon it holds as you draw
it. This effect lasts for 10 rounds. A sacred
scabbard functions only for good-aligned
characters.
Prerequisites: Craft Wondrous Item,
bless weapon.
Cost to Create: 2,200 gp, 176 XP,
5 days.
Since MIC is a later book, use this in preference to CW. Differences are swift action to activate, only functions for good aligned characters, and specifically says it lasts for 10 rounds (I don't know how long the CW lasts)
Sacred Scabbard (Complete Warrior, p136; DotF, p26)
Sacred Scabbard: This item has a varying appearance.
When first found, there is a 25% chance it
appears as a dagger sheath, a 25% chance it appears as
an axe case, and a 50% chance it appears as some sort of
sword sheath. A user quickly discovers, however, that a
sacred scabbard can change shape to fit whatever dagger,
sword, or axe is touched to it, even making allowances
for double weapons. These scabbards keep any weapon
carried in them clean and sharp. In addition, up to
three times per day, the user may place a weapon in the
scabbard, utter a command word, and invoke bless
weapon on the weapon inside.
Faint transmutation; CL 4th; Craft Wondrous Item, bless
weapon; Price 4,400 gp; Weight 1 lb.
(Note: DotF has a market price of 6,400gp)
Ninja-to Scabbard (OA, p74)
Ninja-to: The ninja-to—a short, straight sword similar to a
wakizashi—is the standard sword of the ninja. True to a ninja’s
methods, the scabbard of the ninja-to is a multipurpose tool. It
is open at both ends, allowing it to be used as a blowpipe for
powders or poisons or as a breathing tube. It is also stiff and
strong, allowing it to be used as the rung of a ladder or even as
a weapon (use the statistics for a club).
Concealable Scabbard (Song and Silence, p37)
doesn't say much about it, but lists it on a table for pick pocket modifiers
+4 to pick pocket roll
You have a concealeable scabbard or other
pockets/straps that aid in concealment
Masterslaying (BOVD, p112, actually a weapon mod but the scabbard is involved)
Masterslaying: This melee weapon comes with a scabbard,
belt hook, or other holder that is keyed to it in a special
way. At the command of the character wearing the scabbard,
the weapon attacks its current wielder with the scabbard
wearer’s attack bonus, and the wielder is considered flatfooted
(no sneak attack is possible, even if the scabbard
wearer is a rogue). If it hits, the masterslaying weapon deals
critical hit damage. This weapon is useful against rogues,
foes that enjoy disarming and grabbing weapons, and in
conjunction with the fleshgrinding ability.
Caster Level: 11th; Prerequisites: Craft Magic Arms and
Armor, animate objects; Market Price: +1 bonus.
False Scabbard Tip (Complete Scoundrel, p108)
False Scabbard Tip: A scabbard can be fitted with a
hollow space at its end that extends a few inches beyond
the tip of the blade it holds. Access to a false scabbard tip
typically requires depressing a button or a latch to unhook
the tip from the sheath.
A quick-release mechanism, allowing access to the
hidden space with only a move action, can be added to
any false scabbard tip for an extra 100 gp.
A scabbard is typically the same size object as the
weapon it holds, and a false scabbard tip has a capacity
two size categories smaller than that. A dagger’s scabbard,
for example, could have a false tip of Fine size, while a
greatsword’s scabbard could be large enough to hold a
Tiny object (such as a dagger).
Price: 10 gp.
mundane scabbard listed as part of CR24 treasure (Draconomicon, p286)
adamantine longsword scabbard set with tiny rubies (7,000),
mundane scabbard listed as part of CR26 treasure (Draconomicon, p286)
6 mithral scabbards set with violet garnets (2,000 each),
mundane scabbard listed as part of treasure type E (500gp) (MIC, p268)
silver-plated scabbard with jet cabochons
mundane scabbard listed as part of treasure (The Heart of Nightfang Spire, p9)
jeweled scabbard (300 gp).
Scabbard of Keen Edges (DMG, p266)
Scabbard of Keen Edges: This scabbard is fashioned from
cured leather and fine silver. It can shrink or enlarge to accommodate
any knife, dagger, sword, or similar weapon up to and including
a greatsword. Up to three times per day on command, the scabbard
casts keen edge on any blade placed within it.
Faint transmutation; CL 5th; Craft Wondrous Item, keen edge;
Price 16,000 gp;Weight 1 lb.
Scabbard Maker is mentioned as a craftsman speciality in DMG2, p92)