Under $100: Investing in bullet journaling. $20 for the book, $15-$20 for each journal I go through, and getting a little nerdy about pens, but still cheap. Bul

Under $100: Investing in bullet journaling. $20 for the book, $15-$20 for each journal I go through, and getting a little nerdy about pens, but still cheap. Bullet journaling changed my life. As a lifelong ADD sufferer and disorganized person, switching to a rich paper calendar system and note-taking system did something for me no clever software ever did. Over $100: 1985 Mossman acoustic guitar ($1600). I'm a serious, lifelong guitar player, and this guitar filled a need I had for a great-sounding, great-playing acoustic for gigging, jamming, and getting knocked around. I love the sound and feel, but it wouldn't cause a nervous breakdown if broken/stolen (unlike my best acoustic guitar).