I’ve suffered through enough Christmases to know that giving an unwanted gift is almost as painful as getting one.
So I perked up when I heard about a free iPhone app called Aha that works a little like Kickstarter—if the gift falls flat, you don’t have to buy it.
It’s one of a new breed of websites and mobile apps that apply Internet-born business models to gift-giving traditions that have worn out their welcome.
Couples planning a post-nuptial getaway, for example, can go to honeyfund.com and crowdsource the honeymoon of their dreams (27,500 newlyweds so far have opted for Italy, 38,000 for Hawaii).
Or they can go to Wedding Republic, which borrows from the Pinterest model, as well as offering cash as an alternative for a gift you didn’t want.
But use these tools wisely. Think twice before you give any site access to your contact list and watch out for steep mark-ups. I thought the Bsteady smartphone car mount I found for $49 through Aha might make the perfect gift until I discovered I could get it from the manufacturer, b_hold, for $30.
[Aha says that in this case, their Bsteady car mount is made out of 3D printed nylon, b_hold’s out of composite rubber.]
Follow Philip Elmer-DeWitt on Twitter at @philiped. Read his Apple (AAPL) coverage at fortune.com/ped or subscribe via his RSS feed. You might also want to subscribe to Data Sheet, Fortune’s daily newsletter on the business of technology.
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