What application launchers are available for Ubuntu?

One that I use and like is Albert.

It's very similar to OS X's Spotlight Search, especially in how it looks, but I've found it to be invaluable if you're a keyboard-heavy power user.

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You have to install it via a PPA (not in the official repos yet):

sudo apt-add-repository ppa:flexiondotorg/albert
sudo apt-get update
sudo apt-get install albert

On the first launch you will have to set the hotkey to launch Albert, but that's fairly easy:

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I've set it to Ctrl-Space.


Docky is a great app, you can install it with:

sudo apt-get install docky

Docky


GNOME Pie is another great one that can be installed with:

sudo apt-get install gnome-pie

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(Launch with CTRL + ALT + A - this hot key is customizable.)


Cairo-Dock is also good, and can be installed with:

sudo apt-get install cairo-dock

Cairo-Dock


Plank is another good one that can be installed with:

sudo apt-get install plank

Plank


Here are some more ways to launch and organize applications:

GnomeDO

sudo apt-get install gnome-do gnome-do-plugins

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Duck Launcher

sudo add-apt-repository ppa:the-duck/launcher
sudo apt-get update
sudo apt-get install duck-launcher

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Launcher Folders:

sudo add-apt-repository ppa:asukhovatkin/unity-launcher-folders
sudo apt-get update
sudo apt-get install unity-launcher-folders

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Slingscold Launcher

sudo add-apt-repository ppa:noobslab/apps
sudo apt-get update
sudo apt-get install slingscold

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