I use a waiting for folder to hold the things I am waiting for that will then be moved or filed elsewhere when they are complete.
For example, I have some outstanding invoices I am waiting for payment on. Once the payment comes in I'll enter it into my accounting system and then file the invoices in the appropriate reference folder. I don't like to put ones that haven't been paid there because I scan and then shred my reference folder contents once a month. I need a quick place to look for any that are past due so I can remind the people to pay up. I also don't like to use the tickler file for them because I never know exactly when I'll receive the payment and It's harder to search for something to find the invoice and process it appropriately. There is no separate project folder for these things either so filing them in project support doesn't make sense.
Oogie McGuire - Mac, iPhone & Omnifocus
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Paonia, CO USA