Get Married Online - Setup a wedding with custom pictures and songs and invite your wife/ man-to-be. After the ceremony, you get a certificate. File for virtual divorce too. - http://www.getmarriedlive.com
I-Thee-Commit - Chapel of love. Virtual vows, wedding, and commitment. - http://friendsandlovers.com/itheecommit/
iROM.org - Announce your real wedding or get virtually hitched. Can be used to declare your love for each other. - http://www.irom.org