As a parent with a full-time job, I usually have a limited amount of time to write each day. What are some tricks I can try to reach a specific word count in a specific time (e.g. 500 words in an hour).

I know I've seen some things like this posted on NaNoWriMo forums, but it seems like those folks tend to offer ideas that increase word count at the expense of quality, like writing out your character's grocery list or having characters mishear one another, requiring them to repeat themselves.