
It's amazing how cheap memory has gotten. They have excellent read/write speeds and as far as I can tell they are built to standard and have good durability. The price is cheap enough to consider them expendable or to lend them (even to less reliable friends). Color coded but you can attach a small sticky label for identification if you wish.

Sandisk Ultra Flair 128 GB Silver USB Flash Drive: Reliable and High-Speed Storage
65 Review

32GB SanDisk USB Flash Drive (SDCZ430-032G-A46)
78 Review

Titan Gray Samsung BAR Plus 256GB USB 3.1 Flash Drive (MUF-256BE4/AM) with Up to 400MB/s Transfer Speed
69 Review

Compact and Convenient: SanDisk Cruzer Fit USB 32GB Flash Drive (SDCZ33-032G-A11)
66 Review

π Seagate Backup Plus Slim STHN2000400 2TB Portable Hard Drive - Black: Your Reliable External Storage Solution
93 Review

π Seagate Expansion 3TB Portable USB 3.0 External Hard Drive (STEA3000400) in Black
60 Review

2 TB External HDD Western Digital WD Elements Portable (WDBU), USB 3.0, black
84 Review

18 TB External HDD Western Digital WD Elements Desktop, USB 3.0, black
95 Review