
Mac has now been used by a large number of users worldwide, I have compiled a list of top 20 Mac apps in this post that will make using Mac more fun for you.
Internet & Web
Camino: This is an open source web browser by Mozilla foundation for Mac OS X. (http://www.caminobrowser.org)
Adium: This is an IM developed for Mac that enables you to connect to multiple IM accounts simultaneously. (http://adiumx.com)
SpamSieve: This is a junk email filter for Mac based email clients. It offers a 30 days trial period. (http://www.macupdate.com/info.php/id/15797)
Cyberduck: A good open source FTP software. (http://cyberduck.ch)
Image and Graphic Tools:
Xee: Image viewing and browsing utility. (http://wakaba.c3.cx/s/apps/xee.html)
Gimp: Photo editing tool for Mac OS, also available for other operating systems as well. (http://www.gimp.org)
Multimedia Apps:
Handbrake: is an open-source, GPL-licensed, multiplatform, multithreaded video transcoder DVD ripper with MPEG-4 / H.264 encoding. (http://www.handbrake.fr)
Audacity: It’s a free and easy to use audio recording and editing tool. (http://audacity.sourceforge.net/download/mac)
Perian: A free and open source QuickTime component for getting support for many popular video formats. (http://perian.org)
Burn: Simple software for burning your CD/DVD on Mac, offers many advanced features. (http://burn-osx.sourceforge.net)
Windows Emulation
Parallels: Lets you run Windows based programs on your Mac in their own window. (http://www.parallels.com/en/download/desktop)
Office Productivity:
TextWrangler: is a good tool for bloggers, you can use it for composing blogs, for writing comments, to compose emails offline and for other text editing purposes. (http://www.barebones.com/products/TextWrangler)
Bean: Create and edit your documents with ease using this small word processor. (http://www.bean-osx.com)
OpenOffice: It is the leading open source office softwares suite, it has softwares for word processing, spreadsheets, presentation, graphics and database. (http://www..openoffice.org)
Online Filesharing
SolarSeek: is an open-source Mac application for connecting to the Soulseek peer to peer network. ( http://www.solarseek.net)
Transmission: An open source Torrent downloader. (http://www.macupdate.com/info.php/id/19378)
Personal Productivity
ScreenRecycler: It allows you to use other computer as additional display for your Mac. (http://www.screenrecycler.com)
Things: Manage your tasks easily on Mac. (http://culturedcode.com/things)
RSS
Vienna: An open source and free RSS/Atom newsreader for Mac OS X. (http://www.vienna-rss.org)
Utilities
Tofo: An application that gives you a more better experience for reading books on you Mac. (http://amarsagoo.info/tofu)
Unarchiver: A replacement for “BOMArchiveHelper.app”, the built-in software in Mac OS X for managing your compressed files. (http://wakaba.c3.cx/s/apps/unarchiver.html)

Hey, great collection of apps!
My suggestion for RSS is NetNewsWire… maybe you can add this to the list? (it’s in active development and gets updated often)
Cheers,
Shifty