Here are some interesting discoveries at Rainbow:
1. wide mouth glass jars for storing strawberries and other fruits. I've found that most items that used to be sold in glass jars are now in plastic (mayonnaise, mustard).
2. electrolyte powder
Instead of carrying heavy liquid gatorade or other sport drinks, you can just take the powder and then later mix it with water. Also great for traveling.
3. sichuan peppercorns
Spices at Rainbow are located in 2 different areas. One near the front of the store for spices in bulk jars. One across from the produce section towards the cheese counter; these are prepackaged by the Spicely company. This is where you can find sichuan peppercorns. They are expensive compared to chinatown (9.4 ounces for $1.89), but convenient.