Question: What is it? (updated)

Answer:
- A writing
- A document
- Nothing
- Something
- A house
- A comfortable house
- Acceptance
- Not a short story
- Notice
- An Offer
- A hand gesture
- A Contract
- Nothing
- Wrong
- Consideration
- Reliance
- A gift
- NO no no no
- A promise
- Mere puff and blow
- A red and green sign!
- A piece of paper
- Well, of course it is, but
- An agreement
- A formality
- It's in your notes!
- It's 12!
- Nothing
- A bargained-for exchange
- Motivation
- A counter-offer
- An announcement
- An invitation to deal
- A role-play
- Nominal consideration
- A moral obligation
- A ring
- A barren cow
- Well, technically, what?
- Enforceable
- Lapsed
- No no, don't use the word "void"
- A condition
- A psychic benefit
- Not enforceable
- Seriousness of purpose
- Some sort of weird freudian benefit
- STOP. Tell me about that.
- That's a conclusion
- Question mark
- It... is... nothing!

More to follow as the situation warrants...
Ed. note - New entries in bold, but the list will always end with the obvious.