

Sumatra PDF Reader is no-frills and distraction free. Even on my ancient PC, it’s fast as heck. I have rather rudely installed it on other people’s PCs, because their slow all-singing all-dancing PDF readers drove me up the wall.
RawTherapee converts “RAW” files from digital cameras to friendlier image formats, and pretty often RawTherapee’s edit is all I need. It’s feature packed, it can do film simulations, image de-noising, tone-mapping, and now it has the ability to do some local adjustments, too. I have several “RAW” converters, including a commercial one, but I keep coming back to RawTherapee as the mainstay, the most productive for me.
I’ve got foobar2000 set up as a pretty plain-looking, non-distracting music player. It’s got great library features, it has a wildly customizable interface, it’s got a plugin architecture to extend its abilities in many ways. It has stayed on my PC for years because of its quiet competence, always serving without demanding my time or attention.
I used to keep my password file and other confidential stuff inside a TrueCrypt virtual volume. Now I use the successor, VeraCrypt. Both have always worked flawlessly; in fact, TrueCrypt is way smaller and I’m not aware of any security issues with it, it’s just not actively developed anymore.

I have a Uni Kuru Toga mechanical pencil that I bought perhaps 20 years ago. For about $7. And it still works great.
Somehow, it’s still $7? How?