I have two WaveLAN/Lucent/Orinoco PCMCIA cards, neither in use right now, but both working properly until I didn't need them anymore, one in a WinBook laptop, one in a minitower case running OpenBSD. I also have a clamshell iBook running MacOS X with its optional WiFi. Recently I got a cheap AP that Robricc recommended and it works great. Prior to that I was working in ad-hoc mode with my OpenBSD machine routing between the wireless and wired LANs (not to mention to the internet).

I've never had a problem with any of it, other than minor configuration issues. I don't bother with WAP, since it's just a delaying tactic and increases configuration headaches. I just try to secure my machines as well as possible. I've never been broken into via the wireless (once when I was running redhat on my router someone came in over the internet, but that was unrelated), but, then, most of my neighbors are over 80.