[ultrasaurus]

Literal beepers were still in use as late as 2012 as backups for on call people, enough so that we supported them at PagerDuty for redundancy (the API was email->provider->beeper)

https://www.pagerduty.com/blog/short-emails-for-your-pager/

[baseballdork]

They're still in use for people who work in SCIFs.