Do you want to bill a client for an expense but not include any time entries or vice-versa? Here's how!
1) Go to the matter and make a new invoice.
2) Click the billable items drop-down list and select what you want to be billed for this particular invoice.
3) Review the billing construction page and hit "Save".
What happens now?
Now your invoice is only reflecting what you wanted to select as billable and you are good to go!