App Update - A simple application update widget, in my opinion, besides currency converter, the only good widget in dashboard. It reads you Application folder against 3 update notifications sites - Apple's official software directory, MacUpdate and Version Tracker. Best thing - it just works - and well.
The Unarchiver - an open source decompressor app. For years stuffit was either preinstalled or a must download on the Mac. Over time the the program gained the usual bloat of over developed applications. Apple has included a built in zip tool for a while but it's file support was limited really only dealing with zip's. The Unarchiver, which is open source will extract RAR, ZIP, 7-Zip, LHA, SIT, HQX and TAR files to name just a few. The app has enough options to do everything you could need. To install, just drag it into your Applications folder, run once to set associations and you're done.
Perian - Chances are you've already got this - if not - get it. Perian is a free, open source QuickTime component that adds native support for many popular video formats. XVID, Divx, AC3, MKV, FLV and even adds subtitle support. The only thing missing is extensive WMV support - for that check the free Flip4Mac.
VLC - if you do find a video that won't play via Perian then VLC should have it covered. If you have these 2 apps installed there are few files you can't play. Personally I find VLC's interface clunky to use but as I say - it will play everything.
MPEG Streamclip - Where Perian is 'the swiss army knife of video playback', Streamclip is surely the swiss army knife of video conversion. It allows for setting in and out points and will read almost every format - from malformed mpeg2 streams to xvids to quicktimes to avi's. I haven't met a clip I can't convert with this app.
TextWrangler - an extremely versital text editor. Made by the company that makes BBEdit, this is a cut down yet surprisingly feature complete version. TextWrangler supports source formatting and is the one stop tool for editing HTML, PHP, plists or just about anything else.
MAX - One stop open source audio converter - it will change anything to anything else. MAX can convert over 20 compressed and uncompressed formats including MP3, Ogg Vorbis, FLAC, AAC, Apple Lossless, Monkey's Audio, WavPack, Speex, AIFF, and WAVE.
Comment by Dave, on 19-Nov-2009 01:19
I prefer to use MacUpdate Desktop to keep my apps updated - the AppUpdate widget only finds about 30% of the updates most of the time, and MacUpdate Destop will automatically download and install everything for me - no need to bounce from the widget to a web page and back for each update.