Oh gosh, I remember in college, playing with PCMCIA cards in laptops, and you'd have to kinda point them at each other. Can anyone confirm if that could be correct, or that I'm actually misremembering something?
https://www-01.ibm.com/common/ssi/ShowDoc.wss?docURL=/common... or https://groups.csail.mit.edu/mac/ftpdir/thinkpad/old-archive...
only picture I could find of one: https://www.ebay.com/itm/0934340-IBM-INFRARED-WIRELESS-PCMCI...
Still you wouldnt be aiming whole computers with pcmcia cards in them, there was a dongle, most likely with a clip or velcro to slap in on the back of laptop screen.
The device in question was only available on appointment, so we only had a few shots at this.
Eventually we went with adding a checksum and resending the whole "packet" (one byte) when it didn't match, because we couldn't get the damn thing to send stuff correctly 100% of the time.