Dropbox - You know why. I guess even if Apple releases its own clone, I’d keep it because of my Windows and Linux friends.
DoThings - My menubar companion to Things.app. Shows me the top item on today’s list (anti-procrastination tool) and allows me to mark it as done and ask for the next one. Also allows itself to be paused.
- When I’m screen sharing on a meeting or talk, I like to be able to quickly shut down all my Adium notifications.
ShiftIt -  Resize windows to take halves or quarters of screens. A must if you work with multiple apps on the same task.
Native VPN - Sometimes I need to connect to universities network in order to download papers or connect to some servers.
Time Machine, Airport, Sound, Battery, Date, Spotlight - All the basics, but I should mention that having the day of the week next to time is really important to me since I usually get all mixed up with dates. I should really start having weekends, so I can track days.
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