For those on reserve with vacation, training, or carry-in trips: On the PBS information screen (once logged on, with all the ALV/high/low/extra x-day info) is a "PBS Reserve Pay Excel Spreadsheet." It's available on both the web and desktop version of PBS.
Once logged on, scroll down below the category information down to PBS Resources. You'll find it under Calculators.
CliffsNotes (formerly Cliffs Notes, originally Cliff's Notes and often, erroneously, CliffNotes) instructions: Select month, fill in ALV and extra X-day (if applicable), fill in the boxes with training/vacation, carry-in value (under 'other') and voila - you have your pay.
Easy (Thank you JB for this and so many other awesome tools)