Techwear Wedding Clothes
The great wearable and interface designer from CuteCircuit developed a wedding dress for a Swedish couple. They build many nice ideas "inside" like environmentally friendly and smart, reversible and reconfigurable. So you can wear it after the wedding too.
But the interactive/wearable part is here:
And at the dramatic conclusion of the ceremony, when the happy couple kissed, two messages containing before unspoken love words were passed from one to the other (one from him to her, and one from her to him). The messages are shown only to the couple through a miniscule display integrated inside the trim of the clothes for absolute romantic-secrecy.
The idea is based on "the secret glove" – read this entry to look behind the idea.
Pictures from the wedding (voyeurs only 
here