The fear that you'll run out of money in retirement is big and real and daunting. Which is why we're always excited to hear about it when someone — somewhere — has a new idea to help us conquer the challenges of making our money last. This week's hero: Morningstar's Head of Behavioral Science, Dr. Stephen Wendel. He outlines how a handful of modest (and specific!) changes, when made simultaneously, can amount to much bigger nest eggs. So, calm your retirement anxieties — and geek out on the research — with us. Then, in Mailbag, we’re discussing 401(k) rollovers, the 5-year rule on Roth IRAs and having a dedicated savings account for healthcare. And in Thrive, how to budget with a cash-only diet.