I have a separate spreadsheet like Erik with serial #'s, price, where purchases, filter size, etc.
I also have a separate spreadsheet with EACH item of gear (camera bodies, lenses, extra batteries, computer, external HDs, etc) and its weight. Then I have 4 columns......backpack (carry on), computer bag (carry on), checked bag and wearable vest.
For each trip, I decide what I am taking, then decide how I will carry it. This way I can manage the weight in both my backpack and computer bags (both carry ons) and what goes in the checked luggage.