ObsidiPlates

Overview
ObsidiPlates is an mod, by Myrathi, providing pressure plates that can only be activated by players.

Originally created as a surprise for Jadedcat, it implements (using original code) a concept she missed from Better Than Wolves (which is why it uses obsidian, specifically).

How It Works
An obsidian pressure plate is a type of switch that can be placed onto a surface of a block. If connected by wire to an object (or placed adjacent to a block that can be powered), it will provide power to that object or block when stepped on by a player and will stop when stepped off. As opposed to wooden and stone pressure plates, obsidian pressure plates will not respond to items or NPCs.