I just received an email invitation to do a survey for Avios.com with the incentive that I'd be entered into a competition to win 9000 avios (2nd prize 7k avios, 3rd prize 4k avios). What they don't mention is that if you complete the survey, you get awarded 100 avios by 1st June. They only tell you that at the end of the survey. The survey only takes 10 minutes. So if you get the invite in your inbox, don't delete it!