Hmm I'm 35 I'll mention some:
1). Party line phones, we actually still had these up to the late 90s. For those of you who don't know what these are, in rural areas you basically shared a phone connection. You could be talking to someone and a neighbor a mile away picks up their phone and can hear and talk to you. Many times they would even start dialing over you(rotary phone of course). Basically like in todays world if someone is talking on the kitchen phone and you pick up the bedroom phone. Only its your neighbor.. and they are an asshole and are always on the phone when you need it. So you had to pick up, hear their voice, put it down etc and check back every 10min or so till they are done.
2). No cellphones. You get stuck somewhere, run out of gas, car breaks down etc your walking. Hope you can find a friendly strangers house to make a phone call from. I still remember the excitement when my spoiled friend got a cell phone around 1993/94 ish, we called from the lobby of a movie theatre. So thrilling "No mom I'm in the lobby talking on a phone." Amazing.
3). Video game related - corpse runs.. ala EQ. Playing SWTOR now and it 'oops you died.. would you like to respawn here?'. Thinking of EQ and the dreaded corpse run, so much content not explored due to dieing and not being able to get your stuff back. Days of playtime could be lost. Never forget the time I glitched off the boat in the middle of Timultours Deep ocean on the way to the expansion islands while using the bathroom. There I was everything gone, a customer rep dragged by body to 'an island in the ocean' and then gave me a loc number.. that was it. It took me 30min of swimming to reach a end level zone island and hunt down my shit. Stuff of nightmares.