How are you feeling today? We built a site called happiily (currently offline) that allowed employees to anonymously answer this in a structured way (yes, no, somewhat).

We found that it produced significant insights into operational issues of our customers.

A site similar to what we built is called TinyPulse.

We decided that as a business our focus was best spent elsewhere but the idea of asking a single question or a simple set of questions was effective.

There are two problems with asking a repetitive question though:

1). Employees will tire of the repetition.
2) Without clear, timely and regular communication from leadership as to how the answers provided are impacting leadership decisions and actions, employees will find the exercise futile.

As this is an area I have a lot of experience with and passion for, I'd be happy to talk to you in a call.