So you have just installed ubuntu and want to know what's next, so open up the terminal (Applications > Accessories > Terminal) and get started...
Install the essential compilation software
Even if you are not interested in developing, you may need these packages in order to install applications by compiling source code.
sudo apt-get build-essential
Add the Medibuntu repositories which will add support for all codecs dvd and audio / video
sudo wget - output-document = /etc/apt/sources.list.d/medibuntu.list http://www.medibuntu.org/sources.list.d/ $ (lsb_release-cs).list
sudo apt-get -quiet update
sudo apt-get --yes --quiet --allow-unauthenticated install medibuntu-keyring
sudo apt-get -quiet update
Install support for playing encrypted DVD:
sudo aptitude install libdvdcss2
Install support for adding multimedia codecs:
In Ubuntu 32 bits: sudo apt-get install w32codecs
In Ubuntu 64 bits: sudo apt-get install w64codecs
Other codecs: sudo apt-get install non-free-codecs
Install VLC Media Player:
It is a multimedia player that plays almost any format of audio and video.
sudo add-apt-repository ppa: n-muench/vlc
sudo apt-get update
sudo apt-get install vlc vlc-plugin-esd mozilla-plugin-vlc
Banshee:
Music management and playback application for GNOME
sudo add-apt-repository ppa: banshee-team/ppa
sudo apt-get update
sudo apt-get install banshee
sudo apt-get install banshee-extension-ubuntuonemusicstore
MPlayer:
MPlayer is one of the most popular media player available on linux , it supports playing all the major audio/video file formats
sudo apt-get install mplayer
Moovida Media center:
Moovida is much more than a simple media player... it is a cutting edge media center bringing the best of the internet to your TV screen
sudo apt-get install moovida
XBMC:
XBMC is an award-winning free and open source (GPL) software media player and entertainment hub for digital media. XBMC is available for Linux, OSX, Windows, and the original Xbox.
sudo add-apt-repository ppa:team-xbmc
sudo apt-get update
sudo apt-get install xbmc
Flash plugin for 64 bit
sudo add-apt-repository ppa:sevenmachines/flash
sudo apt-get update
sudo apt-get install flashplugin64-installer
Install support for Java application
sudo aptitude install sun-java6-fonts sun-java6-jre sun-java6-plugin
Bisigi Themes
These themes can be installed by adding besigi project repository, Open terminal and copy the following commands:
sudo add-apt-repository ppa:bisigi/dev
sudo apt-get update
sudo apt-get install bisigi-themes
Screenlets:
Screenlets are small owner-drawn applications (written in Python) that can be described as "the virtual representation of things lying/standing around on your desk". Sticky notes, clocks, rulers, ... the possibilities are endless.
sudo apt-get install screenlets
Ubuntu Tweak:
Ubuntu Tweak is a must have application for Ubuntu and LinuxMint, it is an application to config Ubuntu easier for everyone. It provides many useful desktop and system options that the default desktop environment doesn't provide.
sudo add-apt-repository ppa:tualatrix/ppa
sudo apt-get update
sudo apt-get install ubuntu-tweak
7zip:
p7zip is the Unix port of 7-Zip, a file archiver that archives with very high compression ratios.
sudo apt-get install p7zip-full
Speed up the application launch
Preload is considered to be read-ahead daemon application as it analyzes the applications which user runs, and on the basis of this analysis it predicts which applications user can run next time and launches these applications in RAM.
sudo apt-get install preload
Now to start preload run the following command in terminal: sudo
/etc/init.d/preload start
Install Ailurus
Ailurus is an application designed for making Linux easier to use. You can use it to install software and change system settings.
sudo add-apt-repository ppa:ailurus
sudo apt-get update
sudo apt-get install ailurus
Install Wine
Wine is a tool that allows us to run Windows programs on GNU / Linux.
sudo add-apt-repository ppa:ubuntu-wine/ppa
sudo apt-get update
sudo apt-get install wine
PlayOnLinux
PlayOnLinux is a piece of sofware which allows you to easily install and use numerous games and softwares designed to run with Microsoft®'s Windows®.
sudo apt-get install playonlinux
A few plugins for compiz:
sudo add-apt-repository ppa:compiz/ppa
sudo apt-get install compiz-fusion-extra-plugins
Skype:
Since Ubuntu 10.04 (Lucid Lynx), Skype is part of the Canonical partner repository.
sudo apt-get update
sudo apt-get install skype
Pidgin:
Pidgin is a GTK2-based instant messenger application. It supports multiple protocols via modules, including AIM, ICQ, Yahoo!, MSN, Jabber, IRC, Napster, Gadu-Gadu and Zephyr.
sudo add-apt-repository ppa:pidgin-developers/ppa
sudo apt-get update
sudo apt-get install pidgin
Emesene:
Emesene is a nice and simple MSN Messenger client. It tries to be similar to the official client, but with a simpler interface and a nicer look.
sudo add-apt-repository ppa:bjfs/ppa
sudo apt-get update
sudo apt-get install emesene
Install Liferea
Liferea (Linux Feed Reader) is an aggregator for online news feeds.
sudo aptitude install liferea
Twitter Clients
In ubuntu is installed by default we Gwibber, but we can install other as:
Oriole
sudo add-apt-repository ppa:effie-jayx/turpial
sudo apt-get update
sudo apt-get and install turpial
Install JDownloader
jdownloader is a great tool to download file from share websites like rapidshare.com and many more
sudo add-apt-repository ppa:jd-team/jdownloader
sudo apt-get update
sudo apt-get install jdownloader
Downloader For X:
Downloader for X is a nice download manager that allows downloading files from Internet , pausing them and downloading them later . It also supports splitting file into number of segments so that files could be downloaded quickly.
sudo apt-get install d4x
Deluge
The Deluge application was designed to be a full-featured BitTorrent client. Deluge uses libtorrent in it's backend and PyGTK for it's user interface, and is currently usable on POSIX-compliant operating systems.
sudo add-apt-repository ppa:deluge-team/ppa
sudo apt-get update
sudo apt-get install deluge
Vuze
Vuze is a bitorrent client that is used to download and share files using the p2p network
sudo apt-get install vuze
Filezilla
Filezilla is the best ftp client for Linux
sudo apt-get install filezilla
Install Chromium
I prefer firefox before chromium but is very useful to have another browser installed.
sudo add-apt-repository ppa: chromium-daily/ppa
sudo apt-get update
sudo apt-get install-and chromium-chromium-browser-ffmpeg-nonfree codecs
Install Shutter
It is a tool that allows you to capture screen, edit and upload them to servers such as imageshack.
sudo add-apt-repository ppa:shutter/ppa
sudo apt-get update
sudo apt-get install shutter
Install burg
BURG stands for Brand-new Universal loadeR from GRUB. It's based on GRUB, and add features like new object format and configurable menu system.
sudo add-apt-repository ppa:bean123ch/burg
sudo apt-get update
sudo apt-get install burg-pc burg burg-themes burg-emu
Install OpenShot
It is one of the best video editors for Linux, it is easy to use and has a large number of effects and transitions.
sudo add-apt-repository ppa:jonoomph/openshot-edge
sudo apt-get update
sudo apt-get install openshot
Backup tool: Deja Dup:
Deja Dup is a simple backup tool. It hides the complexity of doing backups the 'right way' (encrypted, off-site, and regular) and uses duplicity as the back-end.
sudo add-apt-repository ppa:deja-dup-team/ppa
sudo apt-get update
sudo apt-get install deja-dup
To secure a website or a web application, one has to first understand the target application, how it works and the scope behind it. Ideally, the penetration tester should have some basic knowledge of programming and scripting languages, and also web security. 
Gmote turns your Android phone into a remote control for your computer, allowing you to start and control movies and music at a distance. It supports all of the standard remote control features such as play, pause, rewind, volume controls etc. It also has a built-in file browser that lets you view the files that are on your computer and select what you want to play. It's great if you want to sit back while watching a DVD, or control the flow of songs in your favorite playlist. 
Real Media Converter (Rmconverter) is a multi threaded GUI that takes advantage from the mencoder and lame packages to generate wav and mp3 formats from real media files (ra, rm, and ram) and wav files.
