Google Trends

Examples
valentines day	red hat, debian, gentoo, slackware	mothers day, fathers day
imdb.com	wunderground.com, accuweather.com	cnn.com, msnbc.com, foxnews.com

Hot Searches (USA)

1.	solar eclipse

2.	cory booker

3.	billboard music awards 2012

4.	kristen wiig

5.	ring of fire eclipse

6.	bee gees songs

7.	celebrity apprentice

8.	robin gibb

9.	jordin sparks

10.	hare krishna