> you could literally sleep your computer,
Depends on whether your sockets survive that, though. Especially on Wi-Fi, many implementations will reset your interface when sleeping, and sockets usually don't survive that.
Even if they do, if the remote side has heartbeats/keepalive enabled (at the TCP or SSH level), your connection might be torn down from the server side.
Not on a Mac
Yes, by generally I really mean all the defaults are pretty permissive, but I understand some people tune both TCP and SSH on their servers to drop connections faster because they are worried about resource exhaustion.
But if you throw up a default Linux install for your SSH box and have a not-horrible wifi router with a not-horrible internet provider then IME you can sleep your machine and keep an SSH connection alive for quite some time... I appreciate that might be too many "not-horrible" requirements for the real world today though.