For version 1.7:
Values toolbar is shown on the picture:
This toolbar is used for quick selection of various mathematical and physical constants and units.
Simple choose a subject, a category and a value in the lists and a variable will show in your doclument.
Example:
Select the variable Earth_mass as shown on the picture:
Now you can get the value of the variable:
It is very convenient to insert variables and units in any place of the document. Simple locate the cursor in a place and select a varaible in the Values toolbar. Read more »