SmileWidget

SmileWidget is a simple, 100% free widget to embed in your website and get feedback from your website visitors.

It shows your visitors 3 types of smileys: HAPPY, SAD, and NEUTRAL, and your visitors voice their opinion.
It also allows them to answer a Why? question after that, and prompts them for their e-mail if they wish to be contacted.
While SmileWidget can serve as a powerful (and free) website feedback tool, by collecting e-mails it also functions as a lead generation machine.