Adobe Reader  
  http://www.adobe.com

Antivirus/Antispyware for Macs (perhaps necessary someday down the road...)
  Mac OS X anti-virus software: More trouble than it's worth?
  http://edu-observatory.org/olli/hcs/index.html (Home Computer Security)
  http://www.securemac.com/ (Macintosh security and Mac OS X Security)
  http://macscan.securemac.com/ (antispyware)
  http://free.avg.com/download-file-ins-afg-free. Free AVG for PCs

Apple
  http://www.apple.com
  
AppleJack  
  http://www.macupdate.com/download.php/15667/AppleJack-1.6.dmg
  
AppleNews
  Apple
  AppleInsider
  MacFixIt
  MacOSX_Hints
  MacObserver
  MacRumors
  MacWorld
  OSXdaily
  SlashDot_Apple
  ars technia
      
Apple Software & Support, etc.
  http://developer.apple.com/opensource/tools/  
  http://developer.apple.com/opensource/tools/runningx11.html  
  http://osxhelp.com/
  http://safari.oreilly.com/0596006063/macpantherian-CHP-10-SECT-5
  http://support.apple.com/kb/HT1343 (Boot Options)
  http://support.apple.com/kb/index?page=search&locale=en_US&q=
  http://support.apple.com/manuals
  http://www.ifixit.com/
  http://web.ipac.caltech.edu/staff/hoard/mactips/MacOSX_configuration_tips.html
  http://www.apple.com/downloads/
  http://www.apple.com/macbook/the-new-macbook/watch.html#large
  http://www.apple.com/sitemap/
  http://www.apple.com/support/
  http://www.apple.com/support/downloads/
  http://www.apple.com/support/find/
  http://www.apple.com/support/manuals/
  http://www.apple.com/support/snowleopard/
  http://www.dsg.port.ac.uk/~eme/mac.html Astrophysics Stuff
  http://www.macupdate.com/
  http://www.macworld.com/
  http://www.macworld.com/search.html?cx=003198751674731024891%3Aovffo1orlum&q=maintenance&sa=search&client=idg-cse&cof=FORID%3A11
  http://www.osxfaq.com
  http://www.osxfaq.com/Tutorials/
  http://www.westwind.com/reference/OS-X/commandline/single-user.html
 
Command Line
  http://www.westwind.com/reference/OS-X/commandline/
  http://www.commandlinefu.com
  http://www.osxfaq.com/tips/unix-tricks/
  http://www.kernelthread.com/mac/osx/tools.html (old)
  http://www.osxfaq.com/tips/unix-tricks/week104/wednesday.ws
    sw_vers
    system_profiler
  http://www.osxfaq.com/tips/unix-tricks/week18/wednesday.ws
    softwareupdate
    
DiskWarrior, etc.
  http://www.alsoft.com/DiskWarrior/
  http://reviews.cnet.com/8301-13727_7-10422139-263.html?tag=mncol;title
    
GIMP (Open Source similar to PhotoShop®)
  http://gimp.org/
    
Iowa State
  http://tech.its.iastate.edu/macosx/macosx-10.6.shtml
  
iPad/iPhone/iPod Apps (Reviews)
  http://www.appstoreapps.com/most-popular-apps/

Mac Ads
  http://movies.apple.com/ca/getamac/ads/
  http://en.wikipedia.org/wiki/Get_a_Mac
  http://pastie.org/602001.txt
  http://adweek.blogs.com/adfreak/get-a-mac-the-complete-campaign.html

Mac Confguration Tips
  http://spider.ipac.caltech.edu/staff/hoard/pages/MacOSX_configuration_tips.html
  
MacUpdate  
  http://www.macupdate.com/
  http://www.macupdate.com/about/

Mozilla Firefox and Thunderbird (alternative brower and alternative mail client)
  http://www.mozilla.org/products/
  http://www.apple.com/downloads/macosx/internet_utilities/mozillafirefox.html

Open Office (Open Source version of office suite)
  http://www.openoffice.org/
  http://www.tutorialsforopenoffice.org/category_index/wordprocessing.html

Open-source DNS Benchmark Utility
  http://code.google.com/p/namebench/

Opera (alternative brouser)
  http://www.opera.com/download/index.dml?platform=mac

Parallels (virtualization software - multiple operating systems)
  http://www.parallels.com/en/

Ramjet (Mac Memory)
  http://www.ramjet.com/
  http://ramjet.com/imacflat.asp

RealPlayer (Media Player)
  http://www.apple.com/downloads/macosx/internet_utilities/realplayer.html

Show My PC (Remote Access)
  http://showmypc.com/

Simple Help
  http://www.simplehelp.net/

Unix Tools (DMGs, Pkgs, etc.)
  http://sial.org/howto/shell/
  http://sourceforge.net/project/showfiles.php?group_id=146701
  http://www.macports.org/
  http://guide.macports.org/
  http://xquartz.macosforge.org/trac/wiki/X112.3.1
  http://www.macupdate.com/info.php/id/26593/xquartz
  http://www.cs.cmu.edu/~benhdj/Mac/unix.html
  http://www.osxfaq.com/Tutorials/LearningCenter/index.ws
  http://moab.eecs.wsu.edu/~schneidj/mac-os-x-10.3.html

Windows Media Player (Media Player)
  http://www.apple.com/downloads/macosx/video/windowsmediaplayerformacosx.html

WireTap Pro/Studio (If you can hear it... you can record it)
  http://www.ambrosiasw.com/utilities/wiretap/

XV is a powerful image viewer/editor widely used in the Unix world
  http://homepage.mac.com/eric.lee/xv/