

A good problem to have - escapegoat

I have a web app hosted on google appengine.  I built it for folks who suffer from chronic disease (including myself).  Anyway the app has grown to about 1100 users who visit every day and now  appengine wants a couple of bucks every few days to keep the lights on.  Right now the app has no advertisements and is free.  I would like to keep the app free with ads or charge a nominal subscription -- say a buck a year.  I think that certain companies who cater to my disease might want to advertise on it....
I am not sure how to proceed in the best way.( I got in to engineering not marketing/business after college ) Any suggestions on a good way to monetize this thing?
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thiagofm
Put on some(only some) google adsense. They pay really high for any disease
keyword.

