A drop-down terminal can save you a lot of time. Always handy, it appears when you press a combination of keys on your keyboard (usually a plain-and-simple F12 key). KDE has Yakuake. Since some people chose to use only GTK-based applications and are GNOME-bound, similar applications for GNOME users would be Tilda and Guake. They both do practically the same thing, with Tilda being older and a little more advanced than Guake and the latter being a little more faster than Tilda. Pick the one you like best and add it to your startup programs for easy Terminal access.