I own lots of macs -- three intel iMacs, two laptops (a Titanium Powerbook and a modern 17" MacBook Pro, maxed out with the fast hard drive (7200rpm) and 4GB memory).

I have a page with a few OS X tips and tricks here:

http://www.timefold.com/osx/tips

My favorite applications for the mac are (no snarky comments, please):

Internet Utilities

• Skype ( http://www.skype.com/download/skype/macosx/)
  Chat, Voice and Video conferencing
• Firefox ( http://www.mozilla.com/en-US/firefox/all-rc.html)
  Internet Browsing
• NetNewsWire Lite (http://www.newsgator.com/INDIVIDUALS/NETNEWSWIRE/)
  RSS Feed Browser

Office Applications

• NeoOffice ( http://www.neooffice.org/neojava/en/index.php)
  Provides equivalents for Microsoft Office, mostly
• Inspiration $69 ( http://www.inspiredata.com/productinfo/inspiration/index.cfm)
  Lets you create mind-mapping diagrams. Kind of like org charts, but much more flexible.
• @-time ( http://www.vojousoftware.com/products.html#attime)
• Microsoft Office 2004 $169.99 at Amazon.com (http://www.amazon.com/Microsoft-Office-2004-Standard-VERSION/dp/B0001WN0M2/)
  The real deal: Excel, Word, Powerpoint, Entourage

Media Applications

• Transmission ( http://www.transmissionbt.com/download.php)
  Bittorrent Client
• Handbrake ( http://handbrake.fr/?article=download)
  Rip DVDs to AVI files
• Fairmount ( http://www.metakine.com/products/fairmount/)
  Decrypt DVDs so you can make legal backups
• VisualHub $23.32 ( http://www.techspansion.com/visualhub/)
  Convert video media from one format to another (e.g. avi to mp4)
• ThumbsUp ( http://www.devon-technologies.com/download/index.html)
  Make or refresh thumbnails for images
• VLC ( http://www.videolan.org/vlc/)
  Play videos of many different formats
• GiMP ( http://www.gimp.org/macintosh/)
  Photoshop-like application
• Giffun ( http://www.stone.com/GIFfun/GIFfun_by_Stone_Design.html)
  Make animated GIFs
• Comic Life $24.95-$29.95( http://plasq.com/comiclife/)
  Make comics with your photos -- super easy and fun!
• Audacity ( http://audacity.sourceforge.net/download/mac)
  Audio Editor
• Umixit ( http://www.umixit.com/download.html)
  Audio Mixer -- based on Audacity
• Fennel DVD Manager ( http://www.fennelsoftware.com/dvdmanager/)
  Manage your DVD collection

Games

• BreakQuest $19.99 ( http://www.nurium.com/)
  Based on Breakout, but wildly more interesting
• Rocket Bowl $19.99 ( http://www.download-free-games.com/arcade_game_download/rocket_bowl.htm
  Surprisingly fun bowling game

System Utilities

• X Resource Graph ( http://www.gauchosoft.com/Software/X Resource Graph/Download/)
  Show resource usage, with graphs
• Disk Inventory X ( http://www.derlien.com/downloads/index.html)
  Visually show how disk space is being used
• Disk Warrior $99 ( http://www.alsoft.com/DiskWarrior/)
  Repair disk drives with logical data problems
• Carbon Copy Cloner ( http://www.bombich.com/software/ccc.html)
  Makes on-demand and scheduled backups, including bootable volumes

I'm also an active member in the OS X tribe at tribe.net:

http://osx.tribe.net

I attend MacWorld each year... for a few hours... ;-)

I also have learned Objective C and the basics of Mac Application Development; however, it is a significant undertaking to become a Mac developer and I am just beginning. I do however have a significant library of books on the subject including:

• Cocoa Programming for Mac OS X (Hillegass, Addison Wesley) -- the book to have for learning how to program macs. Read it cover to cover.
• Programming in Objective C (Kochan, Developer's Library)
• Building Cocoa Applications (Garfinkle & Mahoney, O'Reilly & Associates)
• Learning Cocoa with Objective C (Davidson & Apple Computer, Inc., O'Reilly & Associates)
• Cocoa in a Nutshell (Beam & Davidson, O'Reilly & Associates)