You can use the PS Libraries feature of PEP2 to copy text into activities. While this is not a global scope, at least you don't need to copy the text into each activity after you make a change.

Since I program units for multiple customers, this can be both an advantage and a disadvantage because the PS Libraries code is public. This means that if I make a library change down the road, older programs might break. I must carefully track my changes.

Another technique is to store the code in a label, probably on a page in the Home activity and execute that code as required in each activity. This can be a very powerful technique because the execute can be conditional. I've used this technique to flip an activity between IR and RS-232.

Finally, you could use the "include" statement. This is similar to the library concept, but the file name can be dynamic. In my case I could use a custom file for each customer.