I too am a Mac user at home. I use Yojimbo as a catchall for important emails and web pages that I "print to Yojimbo). I also save many of these in my email program in appropriate folders (thus doubling my chances of finding something). With documents I am a good filer of information in fairly well organized folders and sub folders.
At work on a PC I don't have an equivalent of Yojimbo (I wish I did and this thread reminds me to look into this further). The corporate email system (Notes) is really non-intuitive on how to save emails in folders that will be available for a long time in the future. The Notes mail database size is limited by the company so files are "archived" without my permission. And yet this does not really work well (and since not under my control I can't attempt to fix). Archives get moved to different locations (server, my computer, various folders) with each revision of Notes and receipt of new computers over time. So I gave up. I am just as good at saving documents so I can find them in the future, I just can't find the email that might have been with them.
I keep a phone log at work and urgent things come in by phone or I can put down urgent To Do items as I have to look at this log regularly. Don't really use stickies on a computer for this stuff.