I often check at the MostFun site(the site with down loadable, ad supported games)
The ads are VERY unobtrusive..and short.
I was pleased to discover a VERY challenging hidden object game there.
It is VERY delightfully done; a clever mix of hidden object AND point and click...(with some mini games thrown in)
I am still on the first level(did I say that it was challenging?)
I had to share it here, as I KNOW so many of you love this game genre.
Oh yes, the name is, "Treasure Masters".
http://www.mostfun.com/Details.aspx?GameID=TreasureMasters
Have fun!