Hacker News on 25 January 2013

• Meet Watsi, Y Combinator's First Nonprofit
• Aaron's Army
• Triumphant motel owner slams Carmen Ortiz
• Valve Pushes Out Half-Life For Linux
• A note from Keith
• Google has indexed thousands of publicly accessible HP printers
• The Bicycle Barometer
• Blowing the Whistle on the Mortgage Bubble
• Adioso is reinventing travel search. Check these never-before-possible searches
• Fuck it, I'll Do This Alone