You're on the go, on mobile data, or WIFI, or even just want the freedom to let your device suspend to save battery life:
On the remote:
$ sudo apt install screen || sudo yum install screen
On your roving mobile terminal:
$ sudo atp install autossh || sudo yum install autossh
Then
$ autossh -C host -t 'screen -xRR'
This will automatically re-attach a disconnected shell session, leaving you exactly where you were, without HUPping the command you were running. This is great for when you're running system updates, or compiling, or anything else that requires a long connection.
Personally I use it to shell into a cloud host, which I then have shells to all my other servers combined into a single screen session so I can hop between machines with CTRL-A #, and I set the window names to reflect the hosts.
For another trick - if you want to be able to shell into your laptop and you don't know what it's IP is, set up a TOR hidden SSH service on it. That will allow you to connect no matter what your IP is. It also makes it possible to ssh between two hosts where neither of them know the other's IP. There will be some latency, but you can always connect directly after you've established what the IPs are. Also very handy if your laptop is stolen since your autossh will connect as soon as they connect to the internet, and you can shred your disks or use x11vnc, your laptop's microphone and camera to spy on their activities, get their public IP, and send the cops their way.