Hi, spotted this in my travels recently, might be of interest to some of you guys.

Controlling Crawling and Indexing
Controlling Crawling and Indexing - Google Code

Robots.txt Specifications

This document details how Google handles the robots.txt file that allows you to control how Google's website crawlers crawl and index publicly accessible websites.
Robots.txt Specifications - Controlling Crawling and Indexing - Google Code

-

Little discussion:
Google's Current Specifications for Robots Directives Sitemaps, Meta Data, and robots.txt