Lime juice makes things taste fresher. I use it for drinks, salsas, relishes, soups, and sauces. You want some give to your limes - firmness means the inside is dry - and they'll stay softer longer if you don't refrigerate them.
Charcoal or gas. Both give excellent results, so choose the one that best suits your style of cooking.
A molcajete is a stone mortar and pestle from Mexico. They're great for grinding spices and making salsa and guacamole because they give everything a nice coarse and rustic feel. I've never collected anything, but I think I might start collecting these because each one is decorated differently.
