Hacker News on 18 January 2013

• Stripe Checkout
• A time for silence
• U.S. Senator Questions Attorney General about Aaron Swartz
• Twice
• A cry for help
• Your Mac Keeps A Log Of Your Downloads
• Nokia releases 3D printing files for Lumia phone cases
• ML researcher replies to request to review paper for closed journal
• The Simple Math Behind Early Retirement
• Mathematicians aim to take publishers out of publishing