Save or Splurge: Tote Bag
I love tote bags. If I let myself go, tote bags could easily become an addiction. In my defense, totes are extremely useful and can be very reasonably priced, which is why totes are a major save for me. Canvas totes like this Green Kiwi Tote from chingstote on Etsy is a perfect for everything from books to groceries. These are the totes where I will look for the biggest savings.
I also like more structured totes for carrying my laptop, books, or even all the things I will drag around on a weekend vacation, but these shouldn't cost a bundle either. I've purchase several quality totes from Target (look for clearance).
If you watch end-of-season sales you can even find lovely leather totes at great prices. My mother found a stunning leather tote for $30 from over $100. However, those pretty, pricey totes can be tempting...