Prompted by Hendrik’s recent switch to a Mac (good boy!) I decided to compile a list of utilities, both commercial and free, that I use on Mac OS X. I’ve been wanting to do this for a long time, and this is as good a reason as any. If I manage to update this regularly, I’ll link to it from the front page. Note that I have at the moment not included any of the multitude of command line applications and libraries I use, as well as Microsoft Office or Lotus Notes (both in heavy usage here as well).

	Needless to say, Emacs is the most important application in use on my box. Recommending it to anybody is something I try to avoid at all costs, since the learning curve is steep and I don’t want to be the reason for people’s bitching. If you can take some pain, though, it’s definitely worth ‘getting’ Emacs — you’ll never go back to anything else. You won’t even be tempted.
	Quicksilver is the most useful and the most unusual OS X open source application I know. It’s an application launcher, and much more; every day, you can discover a new bunch of features that make your life easier. If you don’t use it yet, you’re missing something.
	I’m a very heavy shell (bash) user: I much prefer doing a lot of file-related work here rather than using the Finder (or even PathFinder, see below). Combined with the open command, a semi-intelligent find beats most WIMP actions you can think of. Apple’s Terminal.app is OK, but not great; iTerm (which is open source) adds a nice graphical touch (such as transparency) and a bunch of other useful features, like tabbed sub-windows.
	NetNewsWire (or NNW, as most people call it) is a very decent RSS and Atom aggregator, with a very well though-out user interface. The developer, Brent Simmons, is extremely responsive to bug reports and suggestions, runs a very open beta program, and in general should serve as the role model for independent software developers. NNW, like many great Mac applications, is commercial. There is a free (as in beer) version, NNW Lite, but Brent definitely deserves that you purchase the professional version (which I did).
	OmniGraffle, from The Omni Group, is a superb grapics (or diagramming) software; you might call it Visio without the 80% of power features you never use anyway, but with a superb UI. I don’t think anybody else (besides, possibly, Apple) produces software that shows so well how cool OS X is. OmniGraffle comes bundled with Panther, IIRC, an upgrade to the commercial version is probably a good idea (although I haven’t done it yet).
	Ecto is the weblog editor for OS X; it’s totally, absolutely great. (This is one of the applications that, when Windows users watch me using it, makes them want to have a Mac.) It’s commercial, low-cost software, also done by a single developer. Buy it.
	Proteus is my multi-protocol IM client of choice; it’s commercial, again. After playing around with some alternatives, such as Adium, I stuck with this one because it produced the least amount of problems. This might have changed in the meantime, though; since Adium is open source, it may well be worth a look again.
	I don’t really know how it works, or what exactly it does, but SSHKeychain prevents me from having to enter SSH passwords all the time.
	I mostly use Apple’s Safari, the browser that comes with the OS — it renders sites beautifully, and with Saft it’s extremely usable. But it’s nice to have an alternative browser around, and I much prefer Camino (which has a Cocoa UI) to Firefox. They share a rendering engine, so stuff that display correctly in Firefox works in Camino as well. Websites that can’t be viewed in either of them are not worth looking at, anyway.
	Eclipse works very nicely on OS X; it doesn’t really feel that native, but then again, it doesn’t do that on any platform I know. I use it for the occasional Java stuff; if I were still developing heavily (which I don’t currently do), I’d take a look at IDEA as well (last time I looked, it wasn’t that great on OS X.
	CocoaMySQL is an app developer’s UI to MySQL; sometimes a little buggy, but very usable overall.
	I wasn’t sure whether to include this, since I seldomly use it; still, Scheme is a great language, and DrScheme is a great environment to learn it. And since I found it while scanning my app directory …
	OmniDictionary is a nice, small, free utility that does Dictionary lookups.
	I bought PathFinder some time ago; it’s a more fully-featured replacement for the Finder. Although it’s definitely more useful, I found out that I don’t really use it that much. If you’re a mouse man (or woman), though, you should take a look at it.