Go paperless. Just about every financial statement or bill can be obtained and paid electronically. You can save them to your hard drive (and back them up, too!) for your own recordkeeping. This means that you won't have to file these documents in your desk, stash them when company arrives. You also won't accidentally throw them away or spill anything on them...not that I would know anything about gravy-stained brokerage statements...
Reducing your use of paper at the office also helps you to keep your desk organized. Scan documents into .PDF files and save them on your computer, rather than in piles on your desk. I've found it much easier to organize files on my PC than on my desk. Even when I don't organize them well, searching on my computer's easier than rifling through a pile. When you receive a document as an email attachment, review it on your computer and print only if necessary.
Freecycle your junk. The Freecycle Network connects people who want to give away stuff and those who want the stuff. No money can be exchanged in the process.
Sure, you can make a few bucks by having a yard sale. But that requires all sorts of non-ADD friendly steps such as pricing your unwanted possessions, hanging up signs, dragging everything outside, and dealing with early-bird buyers. You'll then be tempted to toss unsold merch into the trash (Destination: Landfill) rather than drag it all back into your house.
Or, you can Freecycle your stuff. Just list your items on the Freecycle listserv in your area, and folks will gladly take your stuff and pick it up from your house, too. What's not to love? Thanks to Freecycle, I've found happy new homes for many items I'd had stored away for years.
Stimulate your brain with foot power. Dr. Hallowell and many others underscore the benefits of exercise for the ADD brain. When you have a bunch of errands to do on a Saturday morning, grab a tote bag as well as a portable music player or a friend to gab with, and do your errands on foot. As a result, you'll have toned calves, raised endorphins, and a cheery demeanor for not trying to find a parking space at the Post Office on a Saturday morning. The environment will thank you for reduced consumption of fossil fuel.
Who knew that ADD would be so good for the environment?!