Keep a list of domestic details on your cell phone or PDA
This hack came about as a way to do two things:
a) to empty my head of some of the niggly domestic details that are important enough to remember, but not important enough to merit "active" brain space, and
b) to be able to take advantage of those random times you find yourself in a store and you remember you need something, but you have to know certain details about that item before you can buy it. For example, you congratulate yourself for remembering to buy a new furnace filter, and you find yourself at the hardware store, but you don't remember what filter dimensions your furnace requires. (Opportunity and time-saver lost.)
I'm compiling a list in my cell phone notepad of all sorts of details so I'm caught in that position as little as possible. Battery size and number for favorite toys, brand of husband's razor blades, furnace filter dimensions, light bulb wattages for various fixtures, clothing sizes...etc. Every time I find out a little detail I may need to use in the future (my friend always orders a double cappuccino with extra foam), I make a note of it so I don't waste time gathering that info later (when I spontaneously show up at her house with coffee).
Parenting is full of so many random detours and unplanned stops. Might as well put them to use.
Related: Lots of ideas in the Getting Organized archive