7 Ways That Amazon's New One-Hour Delivery Could Save the Day

— -- Amazon is now offering one- and two-hour deliveries on "tens of thousands of daily essentials," which begs the question, when would you possibly need something that quickly?

The new service Prime Now is available starting today from 6 a.m. to midnight, seven days a week in certain parts of Manhattan. Amazon is rolling out Prime Now in additional cities in 2015. Prime members can download the Prime Now app to be notified when the service is available in their area.

"There are times when you can't make it to the store and other times when you simply don't want to go," Dave Clark, Amazon's senior vice president of worldwide operations, said in a statement. "There are so many reasons to skip the trip and now Prime members in Manhattan can get the items they need delivered in an hour or less."

Two-hour delivery is free and one-hour delivery costs $7.99, in addition to the $99 a year that Prime members pay for things like two-day delivery and streaming video.

Here are some scenarios that show when Prime may be particularly helpful:

1. You Live in a 6-Story Walk-Up Apartment Building

Amazon says Prime Now can quickly deliver products "like paper towels, shampoo, books, toys and batteries." Apartment dwellers who live in tall elevator-less buildings can probably attest to the convenience of having someone walk up and down stairs for you, especially if you just left the grocery store and forgot to pick up sugar or toilet paper.

2. Taking Your Young Kids to the Store Is a Major Production

Amazon probably knew what they were doing in launching Prime Now at the start of winter. Bundling up your tantrum-prone toddler in scarves and boots in the snow doesn't seem worth trekking for the birthday card you forgot to bring home.

3. You Need a Really Large Item Pronto

Large items can be delivered right to your door in under an hour such as big-screen televisions, a spokeswoman for Amazon told ABC News.

Say you're hosting a film premiere of your indie film and an influential film critic is in attendance. There you are with Rolling Stone's Peter Travers in your living room as your butler pours champagne for your guests. But lo, the butler trips on your bear-skin rug and spills the wine over your TV and media set. Time to turn to Prime Now.

4. Last-Minute School Items

Parents or students can forget items needed for a project or even holiday gifts for the teachers.

5. Baby Things

Baby formula and diapers are among the things that a parent, new or seasoned, may forget when supplies are running low, yet need on a daily basis.

6. Perpetually Tardy People

Prime Now could be helpful if you're in the middle of a conference call or you're multi-tasking while prepping dinner, and you realize you forgot to pick up something at the store. Or it's late at night and you realize you don't have lotion or tights to wear tomorrow. It happens.

7. Medicine

If you're nursing a cold and don't want to leave your home, you can order items like Advil PM. Problem solved. Good Night.