YaKuake is inspired from the terminal in the Quake game: when you press a key (by default F12, but that can be changed) a terminal window slides down from the top of the screen. Press the key again, and the terminal slides back. It is faster than a keyboard shortcut because it is already loaded into memory and as such is very useful to anyone who frequently finds them‐ selves switching in and out of terminal sessions.
YaKuake Homepage: http://extragear.kde.org/apps/yakuake/
shibu@shibu-laptop:~$ apt-cache search yakuake
yakuake - a Quake-style terminal emulator based on KDE Konsole technology
yakuake-kde4 - a Quake-style terminal emulator based on KDE 4 Konsole technology