VWO - Use VWO to tweak, optimize & personalize your website with minimal IT help.
Guess The Product - Provide quick, valuable feedback by guessing a product based on its landing page. You'll get max 40 seconds and 140 characters. Help out others and they'll return the favor.
Optimizely - A/B testing you'll actually use.
Whystle - Get an alert when products you use are recalled.
Crazy Egg - Through Crazy Egg's heat map and scroll map reports you can get an understanding of how your visitors engage with your website so you can boost your conversion rates.
Pandora - Pandora Radio is a free (ad-supported) internet radio founded in 2000.