How do I install CrashPlan with a Unity Launcher icon?

Download CrashPlan for Linux, saving the .tgz archive on your Desktop.

Double-click on the file to open it with Archive Manager, then extract it to the Desktop. You should have a folder now named 'CrashPlan-install' on your Desktop.

Open the Terminal and navigate to the folder containing the installer. Run the install script, using the default choices:

cd ~/Desktop/CrashPlan-install
sudo ./install.sh

After it finishes, you need to do three things.

1. Edit the .desktop file (to make it compatible with the Unity Launcher).
2. Copy it to .local/share/applications.
3. Drag it from .local/share/applications onto the launcher.

Edit the .desktop file first:

gedit ~/Desktop/CrashPlan-install/scripts/CrashPlan.desktop  

Add the line 'StartupWMClass=CrashPlan' at the end, so it looks like this:

[Desktop Entry]
Version=1.0
Encoding=UTF-8
Name=CrashPlan
Categories=;
Comment=CrashPlan Desktop
Comment[en_CA]=CrashPlan Desktop
Exec=/usr/local/bin/CrashPlanDesktop
Icon=/usr/local/crashplan/skin/icon_app_128x128.png
Hidden=false
Terminal=false
Type=Application
GenericName[en_CA]=
StartupWMClass=CrashPlan  

Save, and exit the text editor. Now copy the file:

cp ~/Desktop/CrashPlan-install/scripts/CrashPlan.desktop ~/.local/share/applications

The last part is the easiest. Open your /home folder in Nautilus, and press Ctrl+H to show hidden files.

Now just go to .local/share/applications, grab the icon with your mouse, and drag it to the Unity Launcher.

Credit to @451F 's answer here, which I based this on.

from the terminal enter:

/usr/local/bin/CrashPlanDesktop

right-click on the launcher in the dock and click "Lock to Launcher"