I have a bad habit of writing on whatever is handy to make notes, keep a phone number, etc. I found a neat free program called Evernote that synchronizes between my computer and my smartphone. You can save text notes, photos, audio notes and videos with it and organize them.
For various documents other documents, use Google Docs, Posterous, Slide Share or Microsoft OneNote. All those piles of paper can be cleaned up in a few hours with these tools.
Get rid of that outdated thermal-paper fax machine, the broken down copier, the old ink-jet printer and the flatbed scanner that takes up too much room by purchasing a good all-in-one laser jet machine.
Rather than keeping entire magazines for reading later, skim through them, tear out what you want to keep and recycle the rest. Even better, scan what you want to keep into your online documents program or your hard drive.
I use one of those expanding files to keep my bills straight every year. I just replace the numbered tabs with the various vendors names. Once a month I file them away. It certainly makes tax time a little easier.