Here are some apps I use or think might be useful as a Mac user (long list!). I use most of them.

Useful Applications for Mac OS X

Mail iCal Address Book Stickies iPhoto iMovie iMovie HD (old) Pages (sorta) Numbers (sorta) Keynote Microsoft Office 2008 (Word & Excel, mostly)

Third-party applications

Adium Adobe Acrobat 8 Pro Adobe Dreamweaver CS3 Adobe Illustrator CS3 Adobe InDesign CS3 Adobe Lightroom Adobe Photoshop CS3 Adobe Reader 8 Aperture Applejack (may not work with Leopard) AutopanoPro Azureus Canon Utils Capture One Carbon Copy Cloner Chicken of the VNC ChronoSync Coda Comic Life CrashPlan Crontooie Disk Warrior DropCopy eFax Messenger FDRTools HDR ffmpegX File Juicer FileMaker Pro 9 Advanced Final Cut Studio FireFox Flexify Flickr Uploader Flip4Mac flvThing Font Finagler FotoQuote Pro Google Earth GPG for Mac OS X Growl HandBrake HBTimer iMediaBrowser iPodDisk iTerm Journler LoadMyTracks MacGPS Pro MacTheRipper Mail Act-On MailTags Missing Sync for Blackberry Missing Sync for iPhone MoviePod MPEG Streamclip NetNewsWire Nocturne Noise Ninja NTFS-3G OmniOutliner OnyX Pathfinder PCalc PDFpen Photo Mechanic Photokit Sharpener Photomatic Pro Pukka Quicksilver Region X Sensus Manager Senuti Skype Smugmug uploader Snapz Pro X SuperDuper! Switch TextMate Throttled Pro (does this work in Leopard?) Toast Transmit Twitterrific UnRarX VersionTracker Pro VisualHub VLC VMware Fusion WhatSize WriteRoom Yojimbo

Preference panes

Afloat GnuPG Growl iStat menus teleport TextExpander