This is a very standard Mexican cocktail. I had my first encounter with it when I was about 15 one summer, while visiting my grandparents. Yesterday I was having a a really crappy day, and decided I needed one of these. "Paloma" in Spanish means "Dove", and is really simple to make.
3 parts grapefruit soda or fresh grapefruit juice
1 part Tequila
Slice of lime
-Serve over ice-
I just used Fresca becasue I wasn't in the mood to squeeze any grapefruits. I just needed a drink. You can also line the glass with salt and listo.