CAPTCHA
I really don't know what you guys are on about.
I've just booked four return flights for Feb 2012. I selected the first route and dates, got the CAPTCHA screen, typed in both words with a space in between, immediately got a choice of flights as per usual, selected them and booked. I then booked the other three with no further CAPTCHA requests. The input of one CAPTCHA took all of 5 seconds extra. If that is beyond your capabilities maybe you shouldn't be considering travel at all.
Each return flight cost less than £30.