SS - don't want to pry or anything really, but have you had a look into google adSence
https://www.google.com/adsense/?hl=en_GB. I'm sure you have , but if not it could be a great money spinner - I only have a small web site - 350 page impressions in 3 months - but i've amassed 9.40USD, so if your getting a lot more traffic then you could make some money to cover your costs, and IMHO it wont affect the site - the picture banners give the best gain.- there is also the option of your members seeing usefull information and randomly clicking on one or 2 of the ads from time to time
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