Recently I ran across a large series of scraper sites that are the ultimate in openly cloaking to the search engines. The pages I see when I view the source are the same pages cached by the search engines, nothing special there so a search engine crawling outside it's IP range to check for cloaking would see the same page.
The scraping to build these cloaked pages came from 184.108.40.206 which is in the cari.net IP range:
NetRange: 220.127.116.11 - 18.104.22.168
Just goes to show that people claiming here in comments recently that "Stealth crawling is necessary to keep honest webmasters honest" are out of their league and don't really know what the score is on the web as the sites aren't honest when they are in plain site, no stealth needed, they worked around it.
Wonder what they'll think up next?