Shared web hosts are notorious for overcrowding their servers. To save money, they are known to put thousands of customers on a single machine. The problem is, this may not be immediately apparent upon signing up and you may not run into problems for several months– after it is too late to get a refund.
Thankfully, there’s a clever trick you can use to find out just how crowded a host is using Microsoft’s Bing search engine. First, you will need the website address of a site using the host. You can always use your own if you’re already signed up. Next, ping the domain and take note of the IP it resolves to.
Here’s where Bing comes in. Go to Bing.com and search ip:x.x.x.x. Replace the x’s with whatever IP you are looking up. This will show you how many sites are being placed on an IP, which may not reveal all the sites on a single server, but should give some sort of indication.
You can also use this trick to spy on competitors hosting multiple websites on a dedicated server. If you know one of your competition’s sites and would like to see if he has others, just run the domain’s IP through Bing as described.
Source | Search Engine Watch