I've been a big fan of Yakuake for a long time. It's a terminal you have open all the time in Linux that is shown and hidden, over any other windows, by a simply hit on the F12 button.
But as of more recent versions of Yakuake it has become really slow. It sometimes take 2-3 seconds from F12 press till you can type on the terminal. So I uninstalled it and tried Yeahconsole but I uninstalled it equally fast as I understood it was broken and didn't work at all despite being in the Xubuntu apt repositories.