A new method for users to scan their pokémon's details via wifi has emerged, Instacheck.
http://www.smogon.com/forums/threads/instacheck-hotspot-a-fast-pokémon-checker-for-xy.3492531/
Something such as a laptop with a wired connection not making use of its wireless adapter can be set up as an access point for your 3DS.
At which point your 3DS connects to the virtual router and you use the Instacheck application to scan incoming and outgoing pokémon during a trade.
If during a trade you simply show a pokémon, the program can report every last detail about it, such as its IVs, EVs, Trainer ID, Secret ID, Trainer Shiny Value and Pokémon Shiny Value.
What is the significance of this? In a nutshell, if you have a ton of eggs, like Timid Protean Froakie Eggs for example, you can check their IVs and Pokémon Shiny Value before hatching it.
If it happens to be a 31/xx/31/31/31/31 Timid Froakie with the ability Protean, and you know its Pokémon Shiny Value, you can trade it to a Trainer with a matching Trainer Shiny Value, who can hatch this amazing Froakie into a SHINY FROAKIE.
If one person is running Instacheck, they will be able to determine their own Trainer Shiny Value with any pokémon they have caught, and likewise be able to determine their trade partner's Shiny Value too with a pokémon they caught.
I found out that my Trainer Shiny Value is 3468. Shiny Values range from 0 to 4095, so on the 1 in 4096 chance that one of your excellent eggs has a Pokémon Shiny Value of 3468, I would be able to hatch it as shiny for you, neat eh?