Super Computer

The Super Computer (スーパーコンピューター) was a compact computer that Sailor Mercury owned which could be used to scan surroundings and analyze data, proving very useful in battle. The computer was given to her by Luna.

The Computer also appears as an item toy, in the packet with S.H.Figuart Mercury.

Manga
Sailor Mercury's Super Computer appears first in Act 03, Volume 01. It gives Sailor Mercury the ability to analyze and solve problems, and can find weak points in enemies.

Anime
The Super Computer was given to Sailor Mercury by Luna in episode 9. It can be used to analyze enemies and other objects upon which data is needed, enabling her to find weak points in her enemies. Amy can also use the computer to communicate with the other senshi through their communication devices, as seen in episode 057.