George W. Bush was busy signing copies of his new book, Decision Points, in a Dallas bookstore yesterday, when something happened that produced this expression. Here are ten guesses as to what it was:

• Someone dared to dog-ear a page in Decision Points.

• A man in line just produced a Yoo-hoo from his pocket.

• A man in line just produced his genitalia.

• Bush saw someone use a pair of Heelys for the first time.

• Bush is having trouble swallowing a pretzel.

• Bush just remembered that he forgot to take out the part about his Michelle Obama dream.

• Bush just realized that he forgot to DVR Glee.

Tell us yours in the comments.