Originally Posted by NewbieRunner

Yes, there is free wifi in the *A Gold Lounge and also in the BMI international lounge (previously No.1 Lounge, now called the Great British Lounge!). This is probably the one you have in mind. Some people prefer the *A lounge while others prefer the bmi lounge. Access rules are slightly different between the two lounges.

The former bmi Diamond Club and Business lounges have been turned into one Business lounge but this is in the domestic part of the terminal. I don't think there's free wifi there in any case.