Please bear with me as I learn this incredibly cool medium on the fly here. I just figured out the Star Ratings, so all entries have now been updated. I am very impressed by the range of ideas -- I hope crowdsourcing is a good thing for the creative artist industry, because it's fantastic for us users.

Back to the issue at hand -- #28, 14 and 11 are the coolest of the cool ideas so far. I really like #9 and 4 also because of their excellent transparency.

Keep in mind my growing realization that the theme of a digital safe (vault) would be ideally incorporated in this button and also into the logo (still to be designed).

Thanks again for everyone's efforts.