A headlamp. Allows me to hike in the evening or night. Super useful to hike in the winter when it gets dark early. It never crossed my mind that hiking in the night was a thing but it's pretty cool and I now do it all the time.

Then maybe my commute bicycle that I bought for $200 and that I've been using almost daily for 15 years. So much better than a car or public transportation (at least where I live).

Then we're getting a bit specialized, but as a guitar player, a Yamaha THR (amplifier for playing at home). Tried many solutions and settled for this many years ago.