It took me a while to learn what I can and can't live without. I guess everyone is different but here's my list of items I can't live without:
1. Good shoes. I don’t need to bring a lot of shoes as long as I have one pair that I can bear to wear all day.
2. A Towelini. When I head to a beach destination, Towelini and a bathing suit is all the clothing I need. It's a towel, but thanks to two long handles integrated into the top, it can be wrapped and tied it dozens of different styles and worn as a dress, sarong or robe (see www.towelini.com). Or it can be unwrapped and used like a beach or travel blanket or travel towel, or it can be rolled up into a soft pillow.
3. A Diva cup. It’s a reusable silicone menstrual cup and generally, once you’ve tried it you won’t want to go back to pads or tampons. It takes up virtually no space in my bag and it beats shopping for tampons while on vacation. I found a retailer near me at http://www.divacup.com/
4. A hat. A hat provides protection from the sun and rain.
5. A reusable shopping bag. It takes up almost no space in my luggage and comes in ultra handy when I pick up more souvenirs than I can fit in my suitcase.
6. Writing supplies. It’s handy for jotting down directions, making lists of places to visit, recording contact information of people I meet along the way, letters home, notes to self, …