Mac OS X only: Those who frequently need a Terminal up and running can do better than a free-floating window that gets in the way. With the Visor bundle installed, your Terminal pops out from any spot you choose.
With Visor and its SIMBL parent package installed, calling up the Terminal causes it not to pop up as a central window, but to slide out from wherever you choose — the top portion of the screen, like a command line/cheat code entry box in Quake, by default. But Visor is totally customisable, down to its exact column and row size, and sticklers for particular fonts and window organisation can set up their Visor however they'd like. By default, the terminal snaps out with a CTRL +` combination, but you can set your own shortcut too.
Visor is a free download and requires the SIMBL package to run. Instructions on installing both apps are offered at the How-To Geek site, linked below.