I've been watching too much anime recently
Zaraki Kenpachi's Eyepatch (Bleach)
This seemingly mundane eyepatch grants the wearer +10 to Body, Pain Resistance 10, and Mystic Armor 10. However, it also suppresses the Magic attribute to 1/3 of normal (round down) and requires the user to hold back enough to make any fight a challenge. Prolonged use of the eyepatch may result in the wearer becoming obsessed with finding strong opponents. Kenpachi's Eyepatch may be removed for the duration of a fight if the opponent is challenging enough. The user's magic returns to normal, and they retain all the eyepatch's bonuses. Failure to replace the eyepatch after the end of the fight causes the user to lose all the bonuses. This can only be used by awakened characters
Gigai (Bleach)
An artificial body. It functions exactly like a real one, and must be attuned to a specific person. That person can use it instead of their real body when returning from astral projection.
Sharingan (Naruto)
a bioware eye that comes alone or in pairs (works the same either way). Allows the user to copy any skill or spell they see used at the skill level of the user, permanently. If the sharingan is not made custom for the user, it causes a great deal of mental and physical stress to use, giving them a -5 DP to all tests until they are able to rest for several days.
Jin's katana (Samurai Champloo): wielding this sword automatically grants the user Blades 7 (Sword +2), and Shogi 7 . It also makes them very quiet and stoic. Anytime the group needs money, they will end up relying on the character wielding this sword to provide.