Necessities For A Lady:

1.) A carpet bag. Maria (Sound of Music), Anne (of Green Gables), and Mary (Poppins) all had one, does that not persuade you enough?
2.) Bobby pins. Ever had a bang issue in 90 degree + heat? Whip out a bobby pin and your bangs are rescued. Not to mention bobby pins can be handy little tools in emergency situations (not sure for what, but I have faith that small, pointed, sharp, metal can have more than hair styling usages).
3.) A handkerchief. Ok, so most people think hankies are a bit unsanitary, but I find them endearing and highly helpful in many situations. Think, a hankie can serve as a Kleenex, napkin, bandage, handy cloth ... though I recommend not using the hankie for all those things at once.
4.) A book. Why you might ask? To occupy your mind in dull situations, an imaginative escape, and to make use of doctor's office or train time. Also, it's much easier to accept people being late when you're engrossed in an interesting book.
5.) Hand Cream and Chapstick. Let's face it, everyone loves soft skin.
6.) Aspirin. You can make many friends by carrying this around.
7.) Good things memorized so that you can repeat them in your head. Maybe it's a song, verse, poem, or something someone said, but it's nice to store it in your mind and recite it to yourself when the situation calls for it (I'd advise silently, or people may think you're crazy).
8.) An umbrella. This would be the part of the list where I typically fail. I'd much prefer getting wet -- really -- but, I still think if we're speaking in terms of ladies, an umbrella should be at hand.
9.) A good luck charm. It doesn't really have to be a charm, but something you always wear that gives you luck and familiarity -- something with meaning. Mine are my rings, I never take them off.
10.) Smoking hot boots. That way, when life kicks you down you can put on your boots and it all feels a little better (or at least looks better).

This list is both ridiculous and silly, but if you too are ridiculous and silly then post more ideas in the comment section. Ladies only, of course. ;)