Clock

Clocks are a form of timekeeping technology the Shire folk; the Hobbits.

Background
The Shire clocks are very important part of Hobbits every day life  as they must keep a schedule of when to have their multiple breakfasts or when setting up appointments with others. The hobbits use the term 'o'clock' (which is probably a translation into modern English) in the Shire reckoning of time. Clocks are considered a sign of comfort in Hobbit life.

Bilbo Baggins kept a clock on the mantelpiece above his fireplace which he and others often placed letters.

Despite the ingenious nature of the technology it has apparently not moved beyond the Shire.

Behind the scenes
Clocks first appear in the Hobbit, but also referenced throughout LOTR by the Hobbits.