In a previous review (of the Mrs. Smith's Elite Diaper Bag) I mentioned that I use a Pouchee Purse Organizer, which I purchased with some gift money (thanks Grandma!) a few months ago. I know it sounds overly dramatic when I say this, but it has changed my life. It is so simple to run errands now that I can carry all my mom stuff in the diaper bag, without actually having to disperse my mom stuff into the diaper bag.
It is basically a mini purse that holds all of the essentials. The one I have has pockets in all the right places (I'm not sure if they're all configured exactly the same way, as it comes in cotton canvas, leatherette, and an "ultimate" version). There are two main sections on the inside, one big enough for my wallet (which is not dainty and small by any stretch of the imagination), and one that holds a small hairbrush, a pocket mirror, lip balm, nail clippers, a nail file, and any other smallish cosmetic thing I might need that day. There are also a few tall narrow pockets that fit a tube of lipstick perfectly (so it doesn't get lost in the bottom), as well as a couple of narrow pockets that I use to hold a spare key for my car, and any store gift cards I may have (so I don't forget to use them). On the outside of the Pouchee Purse Organizer, there are 3 pockets, all big enough to hold an iPhone, one to hold a pen, and several to hold commonly used cards.
One of the great things about the Pouchee is that you can just grab it and go - if you've just got a quick stop and you don't need your whole diaper bag, just grab the Pouchee and go. If you keep your keys on a carabiner, even better - just clip the rings to your keychain and go handsfree. If you are changing purses (night out, without the baby? Why, yes please!) you just pick up the Pouchee and put it into your new purse (or any purse that's not your diaper bag). And then you're done! No panic about forgetting to grab your driver's license from one purse to another, if everything important is in the Pouchee then it's all you need to move.
It's sturdy and well made, and has held up very well so far. I haven't had to wash it, but would assume that since it's made of cotton, I should be able to do my usual routine of putting it through the machine on the Delicate cycle, and then air drying... (don't hold me to that though, as I haven't tried it!)
If you'd like to learn more, check out their website at http://pouchee.com/ or click through on the embedded Amazon link to purchase. It's not dirt cheap, but considering it's like buying an infinite amount of purses, $30 is not bad!