An eagle-eyed reader noticed the poster above offering to match bmi status to Aer Lingus. Useful probably only if you fly to or from Ireland.
The Application form is here.
However, the offer seems to be not quite as great as it might be – they seem to be offering bmi Silver to Aer Lingus Prestige and bmi Gold to Aer Lingus Elite.
BMI Silver members can avail of our Gold Circle Prestige level benefits and BMI Gold level members will be offered all the benefits of Gold Circle Elite membership
The difference between each tier is on this chart from the Gold Circle website.