Our go-to choice for cheap, bulk storage is WD's My Passport 4TB, which Newegg has on sale for $110 at the moment. So do several other vendors, though if you apply coupon 80108EDSS03, Newegg will knock another $10 off the price, bringing the total to $100.
There is a caveat—you have to like the color red, or at least be willing to own a red portable HDD. The My Passport is available in other color options, most of which are also marked down to $110 (from WD's $150 list price), but the promo code only works on the red model.
WD's My Passport is not the most compact option on the planet, but the bang-for-buck is pretty high. We also like that it doesn't require an external power source, and it includes software to automate backups. It also offers password protection with hardware encryption.
You can grab the drive on sale here.
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