TrendSpottr – TrendSpottr helps users discover the most timely and relevant information about any topic from across the real-time Web.
RSS Feeds Hootsuite Plugin – If you use Hootsuite, this plugin is great for keeping track of your RSS feeds all in one place.
Bottlenose – Bottlenose provides social media listening and analytics for marketers, including a free search tool for tracking trending news and topics.
Quora – Quora is a great place to find what people in your niche or industry have questions about – a goldmine of great ideas for content.
LinkedIn Answers – Like Quora, LinkedIn Answers is another excellent source of ideas for content.
Google+ Communities – Join some relevant Google+ Communities to get some content ideas from the discussions taking place.