I went down the rabbit hole of getting WPA2 connectivity on my Amiga 600. It's much slower (around 0.1x) than a wired NIC, but it's a weird sort of flex - modern wifi connectivity without compromising security, on a 33 year old computer.

I found a couple of suitable Prism2 wifi cards for around GBP12 each on eBay.

The challenge is how do you flash the firmware on one of these cards if you don't have a working early 2000s Windows PC with 16bit card slots? The answer is you buy a smashed up old laptop off eBay for peanuts and then spend several evenings working out how to run a Live Linux distro with a working toolchain for recompiling kernel modules. The good news is that I documented the process, which I successfully used on a GBP5 laptop with no hard disk and only 128MB of RAM: