Source: Unearthed Arcana 39 - Feats for Races

Prerequisite: Gnome (rock)

You master the tinker techniques of your people. You gain the following benefits:

• Increase your Dexterity or Intelligence score by 1, to a maximum of 20.

• When you make a check using your proficiency with tinker’s tools, you add double your proficiency bonus to the check.

• When you make a device with your Tinker trait, you have the following additional options for what you make:
  • Alarm : This device senses when a creature moves to within 15 feet of it without speaking aloud a password chosen when you create it. One round after a creature moves into range, the alarm makes a shrill ringing that lasts for 1 minute and can be heard from up to 300 feet away.
  • Calculator : This device makes doing sums easy.
  • Lifter : This device can be used as a block and tackle, allowing its user to hoist five times the weight the user can normally lift.
  • Timekeeper : This pocket watch keeps accurate time.
  • Weather Sensor : When used as an action, this device predicts weather conditions in a 1-mile radius over the next 4 hours, showing one symbol (clouds, sun/moon, rain, or snow) for each hour