6. Agorapulse

Agorapulse can be used to create contests on Facebook, Twitter, and Instagram. It also allows you to create custom queries for certain keywords on Twitter and track the buzz surrounding the topic.

Analytics clearly shows you which of your most successful FB posts and tweets are performing well. To get a better idea of the most popular topics, you can look through the posts from the past weeks and refine your keyword list.

7. Topsy

Smart marketers can also use Topsy. You can search for specific topics with this tool, or search for trends that are based on a specific date, time, or location. To determine social sentiment towards them, you can create alerts, monitor and analyze the trends.

Let's say you have a campaign plan that focuses on next Christmas. To find useful keywords, you can simply go to Topsy and search for trends in the Christmas past. This type of search is impossible with other tools.

8. Reddit

Reddit is an extremely popular website where people have heated discussions on all topics. You can vote up or down the topics and only the ones that have the most "upvotes" are displayed on the homepage. Reddit's homepage is a good way to get a sense of what's hot right now.

Its subreddits are the best way to get rich. Instead of exploring the homepage, simply search for subpages that focus on specific topics and provide more detailed insights. Here you can search for subreddits that are related to your topic.