VITBOOST Magnesium Glycinate 500mg, 120 Capsules for $9.95

This is a 120-count bottle of VITBOOST Magnesium Glycinate (500mg per serving) marked down to $9.95, which the listing shows against a $19.95 list price. At that price it comes to about 8 cents a capsule, and Amazon has it shipping free and arriving the next day for many addresses.

Magnesium glycinate is one of the more digestible forms of magnesium, and shoppers commonly reach for it to help with sleep, muscle cramps, or general stress support — this listing's reviews lean heavily toward people using it for exactly that. At under $10 for roughly four months' worth of capsules (one per day), it's a low-risk way to try the supplement, especially since it's non-GMO and third-party tested. Just note it's sold by a third-party seller (Vitboost) though fulfilled by Amazon, and like most supplements it's marked non-returnable for food safety reasons, so it's not a purchase to make on a whim if you're unsure it'll agree with you.

There's also a 240-count size for $18.95 if you want to stock up, plus a Subscribe & Save option that can shave off more with a clipped coupon. As always with supplements, the FDA hasn't evaluated these claims, so treat it as a general wellness aid rather than a treatment.