See any interesting stories in the Magic Shops? In this town, they also have a magic shop, that sells mostly the same products as all the other ones, but one crucial thing is different about this one, every change these products make, the users and everyone else will be unaware of them.
The shop is crowd sourced, and has the most popular items requested by people, and they'll make it so you can use it unaware of the changes, and go wild without a worry.
The Rules:
Step 1: Take an existing thread, and tweak the rules of it a bit to make the product 'unaware'
Step 2: Write a chapter explaining the rules of this new item, or maybe write a few to introduce a character as well.
Step 3: Enjoy!
Have fun roaming the halls of this store, and I hope you enjoy your purchases!