Here are some pretty cool little tools and websites you can use to spy on your competition to find out: Exactly what keywords they are ranking for Their ad copy What there bidding on How much there paying Split testing data Server info And more.. SEMrush.com I am sure a lot know of SEmrush, but if you doing ANY type of SEO this is a great intelligence tool to have at your disposal. SEMrush allows you to go into new traffic opportunities you may never have thought of. SEMRush also allows you find out exactly which keywords your competition is bidding on, their PPC ads, the exact ad copy their using, how much they’re paying, and much more. Go back in time A pretty cool little tool is the Wayback Machine found at archive.org Basically this tool will let you see what websites looked like over time. This tool can actually uncover some priceless data and let you see years of split testing. Builtwith.com Find out what tech a site has such as Hosting provider, Server information, Analytics tools, Advertising Partners, Content Delivery NetworksAnd much more. What theme is that? Have you ever landed on a website and wondered what wordpress theme they were using? With WhatWPThemeIsThat.com you can find out exactly what theme they are using along with which plugins they have installed. Pretty cool. Fireshot This is an awesome firefox plugin and is a perfect tool when you are doing research that will quickly allow you to take a snapshop of any webpage that is online and will also allow you to make notes about the page. Flippa.com Most everyone knows about flippa.com for buying and selling websites, but this can be a treasure trove of information on your competitors. When someone is selling a websites is when they will divulge tons of valuable info. They will reveal exactly how they are making money with their site and exactly how they are driving traffic to it. If you browse different auctions you’ll often get access to their Google Analytics, Adsense Revenue top keywords and much more. It is really great if you want to see good business models and what is working right now.