Oh indeed, there is huge ammount of creatures that drops items (equipment) they wear and even more creatures, that has visible it's creature products on it's sprites. For example Sparkion was completely divided into creature products representing parts of his bosy. Not enough room to show all of examples :D
I'll try to add some of mosters that are still interesting but weren't shown before:
Our old "friend" Orc Spearman
has visible Spear
in the sprite,
Ogre Brute (as well as Animated Ogre Brute)
or Ogre Ruffian
drops Ogre Klubba
,
Ogre Shaman
and Ogre Sage
wears wisible Shamanic Talisman
,
Moohtant (also Animated Moohtant, Bullwark or Moohtant Wallbreaker)
drops Moohtant Cudgel
,
Mooh'Tah Warrior
wears and drops Cowtana
,
Glooth Golem (also Glooth Fairy)
has visible Glooth Injection Tube on his back
,
Draken Warmaster
used to fight with his Zaoan Halberd
, which you can loot from him,
Barbarian Brutetamer
wears both Mammoth Fur Cape
and Brutetamer's Staff
,
Enlightened of The Cult
wears and drops Cultish Mask
,
Island Troll
fights with his Marlin 
Diabolic Imp (also The Imperor)
holds Pitchfork 
... and finally Merlkin
is using his Banana Staff
during fight.
Fire_Dragon mentioned about deeplings, but there's an analogy with Deathlings, which have very similar sprites. I have to mention, that high class lizards and Lizards Chosen wear huge ammount of their own creature products (included parts of weapons).
I think there is still a lot of creatures to add :)