These items are either common to most space-faring races, specific to one race or unique.
Ablata weed
This Nartec plant can be processed into a
powerful muscle relaxant. Jake describes its effects on him in Animorphs #36: The
Mutation.
Force Field
Most spacefaring races have force field technology. Defensive factors vary from +1 up,
depending on the size of the force field generator. Ax notes in Animorphs #9: The
Secret that it's possible to cast a shadow in a force field. Any solid object in
place when the force field is activated will cast a shadow where it intercepts the field.
Even something as small as a pine needle can do this without being damaged. Once in place,
though, the force field can't be penetrated by a material object unless it's defensive
factor is overcome.
Hawjabran Freighter
From Animorphs #8: The Alien we learn that the USS Enterprise-D from
Star Trek looks something like one of
these.
Ixcila
Looking like a glowing green liquid, this Arn
artifact is the stored memory engrams of a sentient being. As seen in Animorphs #34:
The Prophecy, the Atafalxical ritual can restore it to life.
Ramonite
This metal can open or close, be opaque or clear, based on molecular realignment. Yeerks
use it to imprison Ax in Megamorphs #1: The Andalite's Gift.
Skrit Na Saucer
These are the classic flying saucers of UFO lore, disc-shaped and surrounded by
multicolored blinking lights. From The Andalite Chronicles we learn that they
aren't as fast as Andalite fighters, though they do have zero space capabilities.
An intelligent being holding the Time Matrix can move through time and space at will.
Under some circumstances the Time Matrix can even create a pocket universe. The best
references on the Time Matrix are The Andalite Chronicles and
Megamorphs #3: Elfangor's Secret.