sudo apt-get install tilda
It has nice features like transparency making it look kinda cool on your desktop, the F1 button lets Tilda scroll up and/or down, its a must have app for the command line user on Gnome and XFCE4.
For KDE there is Yakuake, similar application available in universe for kubuntu:
sudo apt-get install yakuake.
- Tectonic’s story on Tilda (Inspired me to try Tilda)