A penny for your thoughts — or 10 million for Tim Cook’s? The Apple chief executive is donating an hour-long lunch at the company’s Cupertino headquarters to raise money for the nonprofit Robert F. Kennedy Center for Justice and Human Rights. Bidding through online auction site Charitybuzz has reached $50,000. ChannelAdvisor Chief Executive Scot Wingo is in the lead with 19 days remaining. The estimated value is pegged at $100,000 — though last year’s charity auction for the same item raised $610,000 for the international rights group.