A few things:<p>- A slow cooker. It makes cooking meals completely effortless: just add ingredients and come back 8-10 hours later.<p>- Sleep eye cover. Particularly a black/dark one that completely blocks out light. It really improves the quality of your sleep.<p>- Coffee grinder. Freshly ground beans are leaps and bounds better than pre-ground stuff. It's akin to the difference between Taco Bell and an authentic Mission burrito.<p>- A Kindle (I think they're less than $100?). I end up reading much more long-form content.
I'll repeat one of keiferski's responses and add another related to food:<p>- Slow cooker<p>- Instant pot<p>Between the slow cooker and instant pot it's harder to make an excuse not to cook dinner even when we're really busy. Cooking with these we have also gotten better about buying raw ingredients to cook with, versus packaged or pre-made foods. This has led to <i>much</i> healthier eating in our home and improved health for both me and my wife.<p>Non-food:<p>- YNAB. I was reasonably disciplined about money before getting it, but definitely improved after. And with getting married, my wife and I have very different approaches to money, it's helped us to stay on the same page. We've resolved our differences by throwing a chunk of money at a generic pot for her to use more freely, but still within a reasonable limit.<p>- TRX. Not normally under $100, but I got a good deal on it via a sale. Made body weight exercising <i>much</i> more interesting than what I'd been doing before, and scalable (especially useful after a shoulder injury where I couldn't do a regular push-up for a few months). You can make your own version cheaply.<p>- Merrill Barefoot series running shoes. These hover around $100, but when I got them and started running in them I had no shinsplints compared to previous running shoes. I had never been able to run for fitness before I got these, and then I went on to run a half-marathon in them. You do have to ease into it though, and if you have bad form (how you land on your foot) you will probably injure yourself.
A kettlebell and a "Simple and Sinister" [1] book by Pavel Tsatsouline. Great (and relatively safe) way to get your fitness on the next level.<p>[1] - <a href="https://www.amazon.com/Kettlebell-Simple-Sinister-Revised-Updated-ebook/dp/B07ZQKWMKR/ref=tmm_kin_swatch_0?_encoding=UTF8&qid=&sr=" rel="nofollow">https://www.amazon.com/Kettlebell-Simple-Sinister-Revised-Up...</a>
Micropore tape so I can tape my mouth shut overnight and avoid sleeping through the mouth.<p>Sounds weird but I don’t have to wake up in the middle of the night to drink water anymore and I also don’t wake up with my mouth/throat super dry.
Halo sleep sacks for a infant were a life saver. Other than that usually under 100 it’s just stuff that does the job of a 10-20_$ tool just does it really well.