Please steal these ideas as I will never do anything with them:

A horror film where you can only see the monster when your eyes are closed.

Machines can talk.
2 lifts next to each other: Oh they pressed the button I’ll go! Oh no I’ll be faster, no let me go, I’m coming!!!, I’m coming!!! BING. BING. BING. Bing bing.

A library where everyone has a shelf for their own books, so you can rent them out and share them with the public (possibly for a cost, a portion of which goes to the library, or the whole thing is just subscription to have and take books).
Also means you don’t have to store your own books.
Also maybe it’s just somewhere in-between a library and a bookshop, so you own the book but so do other people?

Poem about your keyboard:
You touch me more than any other.
You tell me all your thoughts and feelings.
My every curve is built to fit your fingers.
You love that little noise I make.
We've shared some of your most intimate moments.

Photoshop - but when you work slowly the colours start going off.

Unicode lisence plates.

A pizza made of croissants.

It’s hard to fire people in The Netherlands. A job application that includes a free assassination voucher.

A website that states each parliamentary decision simply, along with the necessary contact/action to take to protest/support it.

An inflatable sleeping old person that you can sit next to you on the train to avoid getting up for someone else guilt.

Would you rather your breath smelt like faeces, or your voice came out of your anus.