I'm the early riser in our house, so I was more than a little surprised recently when I entered my office around 6:00 AM and found my wife, Sarah, sitting at her computer.

"Listen," she said. "Isn't this the most beautiful rendition of Over the Rainbow you've ever heard?"

The singer, it turned out, was Eva Cassidy. At the time of the performance, Eva knew she had only a few weeks to live. Over the Rainbow obviously had a special meaning to her. It's almost as if she's singing while peering into another world.

(Here's the link if you want to hear for yourself.)
 

Eva, who died in 1996 at age 33, didn't have any desire to be famous. She sang because she loved to sing. But because she sang from her heart with so much passion, she's becoming famous anyway.

Now, here's what this has to do with writing.

One of my goals is a ghostwriter is to help authors position themselves as experts in their field. To borrow a phrase from the title of Steven Van Yoder's excellent book, I want to help my clients "Get Slightly Famous."

But there's a right way and a wrong way to do this. Some people in my profession encourage people to become authors for the prestige alone. One scheme, for example, is to invite ten to fifteen wannabe authors to participate in a collaborative book project.  

Here's how it works. If you're a participant in this collaborative effort, you simply need to write one chapter consisting of one to two thousand words. Your chapter and the chapters submitted by all of the other participants are then combined into one book.

Presto! When the book is published, every one of you can tell the world that you're an author. Not only that, the 250 or so books that you will get for your participation fee will feature your name most prominently on the front cover. People will think you're the principal author!

Those types of gimmicks do a disservice to all concerned. Writing a book for the sake of becoming an author is meaningless. It's ultimately unsatisfying to the writer and unprofitable to the readers.

Yes, I want my clients to gain visibility and credibility. When they hire me as their ghostwriter, I love to see them reap a whopping return on their investment.

But I also want them to be proud of the books they write, which means they must write the way Eva Cassidy sings. They must passionately offer from their hearts something of value to others.  

If you have that kind of motivation within you, I'd love to help you become slightly famous!

 After awhile we went into dinner.

After a while we went in to dinner.

After a while, we went in to dinner.

Thanks for your insightful comment, Michael. You are right, or at least you're not wrong. The Chicago Manual of Style, which is considered by many writers and editors to be the ultimate authority on correct grammar, says the following:
 
An adverbial or participial phrase at the beginning of a sentence is usually followed by a comma, especially if a slight pause is intended. A single word or a very short introductory phrase does not require it, except to avoid misreading.  (CMS 6.25)
 
In our case, according to the CMS, it would be correct to insert the comma. But since the adverbial phrase is quite short, it seems it would also be correct to omit it.
   
Lynne Truss, in her excellent book Eats, Shoots & Leaves, amusingly talks about how strong-minded editors have been known to wage knockdown, drag-out fights over whether particular commas should be inserted or omitted. That's because, she says, the comma has two distinct uses that are often in conflict.

They are

1. To illuminate the grammar of a sentence, and 

2. To point up - rather in the manner of musical notation - such literary qualities as rhythm, direction, pitch, tone and flow.

Truss goes on to say that the trend nowadays is toward fewer commas.  

In our sentence, is a comma needed after the word while for purposes of clarity? Is it needed for the sake of rhythm (i.e., to indicate a pause)?

After waiting a while, we went in to dinner.

The boy picked up his baseball glove and bat.