1. Amarok For songs (Exaile is good...but still ways behind it...)
2. Xine-ui & Mplayer for playing video files (each has its own good; Mplayer keyboard shortcuts just rock....xine-ui never ditches u...plays everything...). And install Gstreamer codecs to see video thumbnails hen you browse files.
About VLC, i could never understand why do people like it. I mean its good, but it doesn't play real media and quick time files, and it also has no good keyboard shortcuts. But then, Linux is all about choices.....
3. Real Player for real media.
4. Exfalso & Picard For mp3 tag editing
5. Abiword For quick word processor
6. Deluge For Torrent Client (ultimate performance, light-weight, speed)
7. Kopete For instant messange ( Piding doesn't has features like Nowplaying track in status, and notification)
8. Brasero For Disk Burning (It does same job as K3B while still being simple)
9. ISO Master for editing ISO files.
10. Picasa & GNU Paint for Images
11. Pytube for downloading Youtube videos
12. dvd::rip for ripping dvds
13. DeVeDe for creating DVD's
14. Gtkpod and Gnomad2 for Media players synchronisation.
15. Pitivi for video editing
16. Wine for running Flashget as Download Manager (believe me, there is no good download manager in Linux as of now).
17. glchess for playing chess
18. Geany for programming