Seen on BYTECellar, the WIFI232 created by Paul Rickards (see his page on the WIFI232) is an electronic card (with an ESP8266 micro-controller) which you connect on any computer with RS232 (DB9 or DB25 with an adaptator) so you can get like a good old modem used with AT Hayes commands to connect to an internet BBS, for an Amstrad Notepad NC100 for example. See this video for using TCP/IP encapsulated with pppd.

You can buy a WIFI232 at Simulant (U.K.), this address was in a comment at BYTECellar.