How often is the name of your brand mentioned on Twitter? Is your official hashtag getting more attention now than it did in the last campaign? Topsy, a feature-rich search engine for Twitter, lets you find out all these, plus a whole lot more.Here's how your business can benefit from Topsy:1. Search: Using Topsy is a breeze thanks to a user-friendly interface. Simply type the hashtag or the name of your brand, select the criteria from the menu and search for your online mentions. Besides, it is completely free of cost. You don't even have to sign up.2. Track tweets by time: Topsy shows you the number of mentions that a particular hashtag or Twitter account has received over a specific time period. You also have the option to specify range and search within that.3. See tweets in a chosen language: You can refine search results to see tweets in only one specific language or multiple languages like English, Spanish, French, Turkish and Japanese.4. Filter tweets by type of media: Are you looking for tweets with links to videos or photos? Take a look at options like photos, videos and links to filter results likewise.5. Identify influencers quickly: Topsy lets you identify influencers of your brand, or a particular hashtag, in a hassle free manner. Simply filter search results according to influencers using a panel on the left. After that, you can choose to get in touch with them, or retweet relevant posts.Here's what some of the giants on the web have said about Topsy:“Topsy knows what you did on Twitter last year.” - USA Today“Topsy operates the world's only index of the public social web.” - Marketwire“Retailers also can utilize Topsy strategically to pinpoint sentiment.” - Retail TouchPointsAll in all, Topsy works great for social media marketers wishing to know the general sentiment surrounding their brand name, account or specific hashtags, on Twitter.