That was quick. Just two days after Apple (AAPL 1.27%) CEO Tim Cook donated a coffee date to charity, bidding in the auction has now broken more than $500,000. Bidding began on April 24 and quickly reached $10,000 within approximately an hour. The "estimated value" of the sit-down was initially pegged at $50,000.

After two days and 75 bids, the current bid is $555,000 as of this morning, or more than 10 times the "estimated value." The auction closes on May 14, leaving 18 days to go. The coffee date will take place at Apple's headquarters in Cupertino and is valid for two people. Cook will sit with the winner(s) for between 30 minutes and one hour, and travel expenses are not included. It is unclear who will pay for the coffee.

Proceeds will go to the Robert F. Kennedy Center for Justice and Human Rights.