The oldest publicly released code of mine is SLIPShuttle, which provided pushbutton connecting to the internet on an Amiga (the cmdline interface was terrible). Written in AREXX https://aminet.net/comm/tcp/SLIPShuttle.lha
The second oldest was ringconnectd, which allows you to "ring knock" your (POTS connected) modem to make it connect to the internet and mail you your IP address. It was VERY handy while I was in college, and apparently it took off in Africa a few years later as their internet connectivity grew. https://www.ibiblio.org/pub/Linux/system/network/daemons/rin...
ringconnectd never answered a call, but rather listened for a ring pattern that you could specify. So what I'd typically do is go to a payphone, dial my line at home, let it ring twice, hang up, get my money back, dial again letting it ring twice again, hang up, get my money back again, then go to the computer lab to wait. My system at home was configured to connect after the ring pattern [ring, ring, delay, ring, ring]. It would then wait 30s, connect to its ISP, and email me its current IP address.
I did it this way because I was already using the terminal for pretty much everything, and we didn't get dedicated machines on campus. So it was better to just hold my work on my Linux machine at home and connect to it from the lab.
My favorite part is when I start cursing loudly "what hipster doofus wrote this pile of steaming horse crap?" as my eyes bleed Ark of the Covenant style from unblinkingly debugging poorly documented code in a company with a huge codebase only to realize a few seconds later that it’s mine from several years back, when I first started. The old “we have met the enemy and he is us.”