In no particular order:

• dplyr: data manipulation package for R. Since becoming familiar with dplyr, hard things are easy and easy things are easy. Tedious things are easy. And everything just looks clean and understandable.
• aeropress: a weird little coffee maker from the guys that make the spinning disks. It makes a single nice cup of coffee, is self-cleaning, and appears to be virtually indestructible (as opposed to the stovetop espresso makers I’ve owned).
• this bookstand: made from clear polycarbonate, has held everything from cookbooks, to textbooks, to laptops, for over 6 years now. Simple, adjustable design and, like the aeropress, appears to be extremely robust.
• arq: a powerful and well-engineered backup solution for the Mac. Does iterative, encrypted, and interruptable backups. I use it to back up all my photos to Amazon Glacier and Google Drive, and all my work files to the lab fileserver. Works silently in the background and encrypts all its backups on the destination. You can set monetary (for AWS) and data (for everything) budgets that it will stay within.