please take a look my new proxy site http://exoticproxy.com you also can test it, is it work or not.. thanks..
scroll down and click the "Click Here For Freedom Surfing" lots of ad blocks!this is the main problem & your main purpose,try to make your site user friendly! Goodluck!
Wow, You really need to put it at the top, noone is going to go through a goose-chase just to browse anonymously. Make it visible, but at the same time not unordinary.
It would be easier if you can put the proxy surf input on the homepage.. (so people don't have to look for it).
From a purely Adsense related perspective, it is quite a good idea. Making the input field quite difficult to find will (in theory) increase your CTR. On the other hand, you could potentially lose a lot of return visitors due to people being unable to find your proxy functionality. They'll take a look at your site, see the ads and no input field and just leave. Perhaps it would be useful if you trialled each implementation? One week make the input field visible and the next hide it. Analyze the data from these two weeks and compare the two. Does your CTR increase when the input field is hidden? Do you receive more returning visitors when it is visible? It could prove to become quite useful.