If you are using LaunchBar 5, you also can add one or more LaunchBar clipboards to the Quick Entry without a script.
1) First, bring up OmniFocus in LaunchBar
2) Then activate the text entry using shift-space
3) The bring up the LaunchBar clipboard history with command-k
4) Select an entry and hit return. To add additional clipboard entries, type the spacebar once and repeat Step #3. The clipboard entry is added to the note field of the Quick Entry window.