I want to understand if it is possible to use WiFi just like a radio to broadcast data, without actually connecting.
Yes, at least some WiFi adapters can. Software used to attack WiFi connections, like aircrack
, does this by listening and logging (encrypted) packets without authenticating to the access point, and then attempting to determine an encryption key. You can just send unencrypted traffic the way you do today, and software could theoretically receive it.
However, this probably won't provide any great benefit. That is, as far as I know, just being connected to a WiFi access point shouldn't generate much traffic, so you could have a very large number of computers authenticated to the WiFi access point -- just set it not to use a password -- without any real drawback relative to having the same machines snooping on unencrypted traffic.
WiFi adapters cannot listen to multiple frequencies concurrently (well, unless things have changed recently), so it won't let you easily receive data from more access points simultaneously, if you're thinking of having them all send data simultaneously.
Open source does help keep games be forward-ported and playable, but I can think of at least a couple of open-source games that I remember playing that I don't see any more.
Nighthawk, an open-source [Paradroid](https://en.wikipedia.org/wiki/Paradroid1 clone, was in Red Hat Linux 5.2, IIRC, but seems to have fallen out of Linux distros at some point.
Lacewing, an Asteroids-genre game done by Linley Henzell, the guy who did Dungeon Crawl: Stone Soup, was definitely ported to Linux at some point, as I remember running it, but I haven't seen it in distros for a long time. A successor game he made, Overgod, does appear to be in current Debian.