Hard disks (HDDs)
Shuck 'em if you got them keeps tracks of external, shuckable hard disk prices, and whether a current sale is a good price historically.
Power Supplies (PSUs)
Linux Tech Tips' PSU Tier List lists best PSUs. Of note that I've purchased:
- EVGA Supernova G3 550W
- Corsair RM850x 850W, 2018 edition