Planet13 - 8:15 am on Dec 23, 2011 (gmt 0)

Time to move my ecommerce and news sections to to ebay.mysite.com and yahoo.mysite.com respectively.

Actually, I have seen something similar to this popping up in the SERPs lately. Not ebay and yahoo, but I searched for a particular forum (now defunct) and many of the top results had used subdomains to, in effect, trick the user into thinking it was the same domain.