Possible Clues:

• ''Apollo 13'' actor
• ''Six Degrees of'' guy
• 'Green Eggs and Ham' as read by actor ___
• Actor famously connected to many other actors
• Famously-connected actor
• 'Apollo 13' co-star
• Crispy actor?
• 'Diner' co-star, 1982
• Hub of a Hollywood linking game
• Founder of the charity SixDegrees.org