[macpug]

Evernote, hands down. I've used this app much more than I ever dreamed. I use it for so many things, it has replaced several apps and made me much more productive.

World of Warcraft would be nice for when I got bored though..... :P

[DKroot]

macpug,

I'm curious about use cases for Evernote. Could you brifely describe what you use it for?

I do have it installed on Mac and iPhone, but the only use case I found for me is to take voice or picture notes on iPhone, and then process them on Mac (and delete them).

[Nelsoneer]

I suppose my desert island app would be iTunes or something of the like, 'cause if I'm on an island, there's no way I doing much work other than building my lean-to and hammering coconuts! Lol :)

[macpug]

@DKroot:
Hi, sure I can give you some of my uses for Evernote. I have several categories of folders where I keep things organized. I have folders for receipts (take photos of receipts or scan them in), to do lists, blog ideas, research, recipes, tips/tricks, jewelry ideas (for my side jewelry business), and errands, to name a few.

I use Evernote on my iPhone mostly for what I call "errand notes" when I am out. If I see something I want to remember later, or something that is an idea for a project, I fire up Evernote's Snapshot note, take a pic of it, file it in "Errand Notes", and I'm done. Then I can pull it up on my Mac later and work on it at home.

I also use it to take a pic of where I parked, to send myself receipts, emails, notices, bills, reminders...really, the list could go on and on. You can literally make it into anything you want. To make it easier, I would suggest you start at the very beginning. Look at Evernote's website. They have some short screencasts and tutorials on how to get the most out of the app. Check it out here: http://www.evernote.com/about/whatisen/video/

Hope this helps!!

[lindaslair]

Photoshop. It completely revolutionized what you could do with a computer. From green text on a black DOS screen to this... WOW.

[trevorsowers]

Technically it's not "third party" but the most important software for me to install would be Aperture. As for actual third party it would be Visual Hub (alas no longer sold but I still have it).

[Woodwork]

Well Xcode is not a third party app. It comes with every Mac it is on the Apple Developer tools disk.
And actually it does everything bbedit does and more. So if you are allowed one third party app and you choose a more advanced text editor you are wasting your choice to make text editing easier not adding function you don't have with the basic text editor like textedit.
I also use bbedit and it is a great tool but you can write scripts in textedit not as easy and it lacks the time saving tools of bbedit or Xcode but you can still get coding done with out bbedit. And if you want to write non-script code that requires a compiler then bbedit is not going to be of much help there but Apples developer tools will and you get those with any mac. (not installed by default but they are on the CD)
So maybe you want to re-think the choice of BBEdit great text editor in fact I would go as far as saying it is the best on the Mac platform but would I choose it as my only third party app? Probably not.
I would bet most creative pro mac users would be lost without the AdobeCS apps. Or publishing pros with out Quark or indesign. It really depends on what you do on on your Mac day to day.
For me it is CAD and design tools but even though I have some expensive CAD apps on my Mac if I had to choose one that I could not live without believe it or not it would be the free version of Google Sketchup. It is not as powerful as Achicad but I can design just about anything with it and it is so easy to using it's Ruby script support I can add functions as well using a text editor :). Hmm Maybe BBedit is not that bad a choice after all.

[Woodwork]

Yeah if Organize data is all you do try doing design work in filemaker.
(by the way I used FileMaker for years it is a great database app but it is not a must have for most but I can see it being indispensable to many.