This is supposed to minimize the chance of people buying elections. Instead it has been used by the Gaystopo to attack all sorts of people including a waitress who gave the widow's mite to Prop 8. The Gaystopo found out and picketed the restaurant where she worked hoping to get her fired.
Eich didn’t donate directly to any campaign. He made a donation to National Organization for Marriage, in support of their efforts regarding Prop 8. So far as I know, that kind of donation is not public, since it was to an organization, not a public political campaign.