Complete list of Useful applications that you should install after installing Ubuntu 11.10

Gstreamer Plugins
Moonlight
Flash
Adobe Reader
Mousepad
Okular
Calibre
Abiword
Koffice
Kchmviewer
GoldenDict
Desktop Recorder

Synaptic Package Manager
NetHogs
DconfEditor
FileRoller(Achive Manager)
Dolphin
Wine
ClipIt
Nokuntu
Screenlets
tint2
Wallch
Classic Menu Indicator
Kate
pyRenamer
Nautilus Action Configuration Tool
Advanced Settings
Firewall Configuration
System Jobs
PulseAudio Mixer
Gnome Alsa Mixer
BleachBit
BitDefender
HjSplit
SysInfo
Activity Log Manager

XBMC Media Center
Radio Tray
VLC
VLMC
Xine
Audacious
SMplayer
Arista Transcoder
Ardour
Adidmux
Openshot
Pitivi
Kdenlive
Audacity
Videoporama
XCFA
Transmageddon
Mixx
Trimage
Cinerella
Sound Converter

K3b
AcetoneISO
ISOMaster


Deluge
Ktorent
qBtorrent

Kget
Jdownloader
uGet
FileZilla
Skype
Teamviwer

Opera Browser
Rekonq
Chrome
TorBrowser

Divel Journal Editor
Blogilo
Akregator

OpenJDK 6
NetBeans
LAMPP
Geany
QtCreator
Glade
Code:Blocks
Mono Develop
Kdevelop4
AnjutaIDE
BlueFish Editor
Eclipse
CodeLite
IDLE
Komposer
Padre
Visual VM
VirtualBox
HexEditor
wxFormBuilder
Android SDK

Blender
Inkscape
Xara Xtreme
Pinta
Gimp
MyPaint
ImageJ
Darktable
Ksnapshot
K3D
Sweethome 3D
Scribus

Nexuiz
Torcs

To get these applications first search on "Ubuntu Software Center". If not found then Search on Google. You can use "synaptic package manager" too. But you have to install it first.