Six years and 2½ games later, this is what I'm using now for game development:

Hardware

• iMac 21.5inch 2011 model with 32GB RAM
• iPod touch 4th generation
• iPhone 3GS

Software

• Xcode
• Adobe Photoshop
• Pixelmator
• Git

Libraries

• C++ STL
• RapidXML
• Sarah Thompson's SigSlot
• Boost