It seems the EU is taking online participation seriously: Help us choose the design of the new euro coin
To celebrate the 10-year anniversary of the launch of Economic and Monetary Union (EMU) and the creation of the euro, all euro-area countries will issue a commemorative 2-euro coin with a common design. It will be available at the beginning of 2009.
A design competition between the mints of the euro area has resulted in the pre-selection by the Mint Directors of 5 designs, presented here. The final winning design will be selected exclusively by your votes via this web page.The selection is open to all EU citizens and residents. Each person may only vote once. A prize of a set of high-value euro collector coins will go to a participant chosen at random from those who voted for the winning design. Voting will be closed on 22 February 2008.
You can view the designs without registering – just click on the 'VOTE NOW' button.
You have to give an physical address and list your country but while the site says "This information is used to validate and record your choice, and to contact you in the event you are selected as a prizewinner", it doesn't say how it will check that you're an EU citizen or resident, or how they'd prevent people voting with other email addresses.
Still, it's an interesting experiment, especially as it will result in a very evident real world outcome.