PDF Booklet printing

Using Adobe Reader: 

Install Adobe Reader on Ubuntu 14.04:
http://ubuntuhandbook.org/index.php/2014/04/install-adobe-reader-ubuntu-1404/
Booklet printing with Adobe Reader:
https://helpx.adobe.com/acrobat/kb/print-booklets-acrobat-reader.html

Alternate ways:

PdfBooklet:
http://pdfbooklet.sourceforge.net/

Ubuntu 14.04 tray icons for Skype and Rescuetime

On a 64-bit Ubuntu 14.04 to be able to see the tray icons for Skype or Rescuetime or other 32-bit application, install the sni-qt:i386 package. Source: Askubuntu.

sudo apt-get install sni-qt:i386

How to install Sigil ePub editor on Ubuntu 12.04

Sigil, the best ePub e-book creation and editor tool I know, has no longer an official Linux version.
However, it is still possible to get a native copy running on your Ubuntu.
Please refer to this askubuntu post if the below method does not work for you (because it is probably already outdated).

On Ubuntu 12.04:
You'll need to add two repositories, one for Sigil and one for a dependency, then update repos, and install:

sudo add-apt-repository ppa:sunab/sigil-git
sudo add-apt-repository ppa:beineri/opt-qt521
sudo apt-get update
sudo apt-get install qt52base qt52webkit
sudo apt-get install sigil

How to downgrade packages?

I upgraded packages from gnome3-team by mistake (forgot to take out the ppa), and I wanted to downgrade them (back to the official stable version).

ppa-purged worked for me in this case:
sudo ppa-purge ppa:gnome3-team/gnome3

I got this information from this superb askubuntu post. 

Dropbox installation on Ubuntu 14.04.2 LTS with problem solving

Somehow Dropbox does not want to work for me on laptops...

so,

1. ) install nautilus-dropbox from apt

sudo apt-get install nautilus-dropbox

2.) solve permission issue (if present):
find out where dropbox launcher is stored:
which dropbox
edit the path you got from which command (for me it is /usr/bin/dropbox )
sudo gedit /usr/bin/dropbox
find the line causing the permission issue (looking at the wrong place for dropbox):

PARENT_DIR = os.path.expanduser("/var/lib/dropbox")

change it to your home directory (the daemon will be installed here)

PARENT_DIR = os.path.expanduser("~")
save the file.

3.) install dropbox from dropbox official site through ppa repository
sudo sh -c 'echo "deb http://linux.dropbox.com/ubuntu/ trusty main" >> /etc/apt/sources.list.d/dropbox.list' sudo apt-key adv --keyserver pgp.mit.edu --recv-keys 5044912E sudo apt-get update sudo apt-get install dropbox

4.) restart nautilus
nautilus --quit

5.) start dropbox with daemon install
dropbox start -i

6.) add notification area to gnome-panel (if not present):
Super+Alt+RightClick panel > Add to panel... > Notification Area

Hopefully, everything is working now without any kind of unexpected messages.

How to install Oracle Java 1.7 and 1.8 on Ubuntu 14.04?

Install Java version 1.7

Install Java version 1.8

via PPA:

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java7-installer
sudo apt-get install oracle-java8-installer

Set Java 1.7 as default version:
sudo update-java-alternatives -s java-7-oracle

To set environmental variables to Java 7, install:
sudo apt-get install oracle-java7-set-default

Configuring Gnome Flashback with Compiz compared to Metacity

1. Install Compiz Config Settings Manager
sudo apt-get install compizconfig-settings-manager
2. Set number of workspaces:
in Compiz Config Settings Manager go to General / General Settings / Desktop Size
set the size you want.
3. Get to know Compiz Plugins
you might find that not everything is installed by default what you want to use. in this case find out which package contains your plugin and install it.