Hashtags are the most common ways for people to categorize their tweets, so it only makes sense that there’s a bevy of sites and services dedicated to the art of tweet tagging. The site #hashtags is a lot like the “Trending Topics” section on the Twitter home page, as it lists the most popular topics at the moment. #hashtags is different, though; its content is restricted purely to tags preceded by #, and it ranks its tags in an ordered list in descending order from the most popular. Each tag is accompanied by a counter displaying the number of mentions, a sample tweet and a graph showing the tag’s popularity over the past six hours. #hashtags’ information can also be sorted into a number of different lists, from trends (what’s popular right now) to the newest tags being mentioned on Twitter. Rounding out the site’s comprehensive content is a search function, which displays a graph, tweets, people and related tags for the terms you’ve entered.