Mac os X sorely lacks a vertical maximization feature for windows. I bind this applescript to a trigger with quicksilver as a stopgap measure. I'm not sure where I got this from but probably: http://hints.macworld.com/article.php?story=20050428173653581

vertmax.applescript

tell application "Finder"
    set {_dx, _dy, _dw, _dh} to bounds of window of desktop
end tell

tell application "System Events" to tell application "Terminal"
    tell front window
        set {_x, _y, _w, _h} to (get bounds)
        set size to {_w - _x, _dh}
        set position to {_x, _dy}
    end tell
end tell