It's called an office manager. Combined with an expense account for the company.
> - App for finding which stores are open at 11pm (or on Sunday in places where most things are closed on Sunday)
It's called Foursquare. Bonus, it does this for a radius around your current location and when it doesn't have official data, it makes a guess based on check-in data.
> - Swarm - Reverse how people get taxis, register that you're looking for a taxi and expose to taxi drivers where all the people are
It's [probably] called the Uber/Lyft interface from the drivers' side.
> - Reverse registry - wedding registries are obnoxious...register your gift so that people don't buy the same thing.
Haven't reached the Omg Everyone Is Getting Married age, but I'm sure this also exists already.
> It's called an office manager.
No office manager I've ever had would purchase anything and then seek divided reimbursement from individuals in the office.
If you know the couple well enough to get a meaningful gift that is not on the registry, go for it, but I've been to plenty of weddings where I was not close enough to the couple to know their tastes/needs for something as personal as homegoods. No one wants to embark on their new life as a married couple with a bunch of stuff cluttering their house that they'll never use and just have to drop off at Goodwill (or worse, go through the hassle of returns - how many different stores would the gifts come from with no registry?), and no one wants to buy a present knowing that's what will most likely happen to it.