One of the best ways is to setup
Google alerts for keywords you are interested in - for example I am interested in Startups, so I have alerts set up for "Startup", "Startup Gurgaon", "Startup India" etc.
Another good way is to use
tweetdeck and setup columns of your interests - it's often interesting to see what people are discovering, sharing and talking about.
Regards,
Sid [CHR]