In this cracker recipe and its variation, you can blend pretty much whatever you like — cheese, nuts, garlic, herbs, and/or spices for starters — directly onto the dough or replace up to half of the all-purpose flour with whole wheat, rye, or cornmeal. Or just before baking, dust the tops with coarse salt, poppy seeds, or spices.
You don’t need any special equipment to make crackers, though a food processor speeds things up a bit. The success of a cracker depends on your ability to roll out the dough until it’s quite thin, 1/8 inch or even less. Flour is your friend, but use only as much as you need to keep the dough from sticking.