Why are Linux, mDNS and AirPrint together
 so important to me?
  
  - 
    My home computing environment: 
    
    
      - Primary Desktop: Apple Mac OS X
 
      - Secondary Desktop: Various flavours of Linux
 
      - Server OS: Linux
 
      - PDA: Apple iPod Touch
 
      - Printer: HP LaserJet 4P / Nano-ITX PC, Debian 5.0 / CUPS
 
    
    
   
  - 
    The iPod Touch uses the stock IOS updated to the most recent version (not
    jailbroken), and I really wanted to be able to print from it.
    
  
 
  - 
    Apple's AirPrint technology for iPhone/iPad is only officially supported
    on a select few newer-model printers.  However, AirPrint relies on mDNS
    under the hood to do it's thing.
    
  
 
  - 
    I acquired HP LaserJet 4P for free (used, with a partially used and an
    unused toner cartridge) in 2001, and it has been working without problems
    ever since.  Until it dies, I have no real desire to buy a new printer.