Kegel balls
Kegel balls do more than most people expect from something so small. Yes, they strengthen your pelvic floor, which helps with bladder control and postpartum recovery. But a lot of women use them simply because they make sex feel better, and that's a completely valid reason on its own. The weighted pressure increases blood flow and sensitivity over time, and some styles vibrate or come in sets with progressively heavier balls so you can actually track your progress. If you've never tried them, start lighter than you think you need to.