Homemade ice packs can be a good, inexpensive way to stay cool as the Pacific Northwest heat wave crests today and Friday.
To make them, you'll need plastic freezer bags, water and rubbing alcohol.
Mix one part rubbing alcohol to two or three parts water in a bag and put it in the freezer. You can double-bag it if you're worried about leaks.
Inside the bag, the water will freeze but the rubbing alcohol won't, so the pack should conform to your body when it's ready to use.
More rubbing alcohol will make the pack less solid, less will make it more solid.
One suggestion - beyond just wrapping yourself in them in the 100 degree plus heat - is to use a pack on your pillow at night to keep cool.
Also remember to put a towel or cloth between the bag and your skin to prevent frostbite.
For more, check out the Homemade Ice Packs section of Education.com.