Is it already possible, or can it be added to the Bitcoin code, to send blocked coins? Releasable under certain conditions?
A quick example:
You sell your house for 10 BTC. I am interested. You ask me a proof that I have 10 BTC. I send them to you, blocked, with an automatic return within X hours.
Possibility 1: We sign the sale and I send a confirmation of the release.
Possibility 2: The sale does not take place and I automatically get my 10 BTC back after X hours.
Perhaps, technically, this could be introduced into the bitcoin technology, but for sure no one will do this, because there are intermediaries and traits who can vouch for you. Although the idea is very interesting and it would be great to see its implementation in another coin.