[Updated] My GTD setup - GMail, del.icio.us, iCal, Treo 650, Mac OS X

Gmail
Labels

• @ACTION
• @DATA/ENTRY
• @READ/REVIEW
• @WAITING FOR

del.icio.us
Tags

• @ACTION
• @READ/REVIEW

Entourage iCal
Tasks Calendars

• Personal
• Work
• Travel
• Birthdays (from Address Book)
• (Holidays, etc.)
• brainstorm
• calls
• chores
• code @home
  
• code @work
  
• decide
• desk @home
• desk @work
• email
• errands
• google
• inactive
• mac anywhere
• read
• waiting for
• web

Notes

• agendas
• checklists
• projects
• reference
• someday/maybe

Treo 650

• Agendus
• Gmail mobile app
  
• Hours
  
• PrayMinder

Mac OS X

• Quicksilver
• Camino
• Missing Sync for Palm OS
• Adium

Other tips

• Reduce the amount of things you carry in your pocket:
• Call all stores with whom you have discount cards. Give them your phone number. Now toss the cards or at least put them in a file and out of your wallet.
• Create uniformity
• Use only one type/color of post-it, pen, and pencil at work, home, and travel. I used to like the fun colors, but this way provides uniformity and prevents you from adding a meaning to the random colored post-its you have laying around. Instead pick a cool color scheme and stick with it. Like all gray post-its and all baby blue file folders or something or another. I used to use all the crappy cheap pens I would get at work, but choosing your own pen and using on a regular basis feels great. And you co-workers won't steal your stuff as much mistaking it for their own.
  
• Make all file folders align either left or right and align the labels all to the left (not centered). Again provides uniformity. Got this from another blog. Can't remember where.