since i haven't uploaded most of the themes, i don't know if everyone knows that.. but LXDE panel supports transparent PNG files i.e. you can have circular or any shape icons you want... just like in "Longhorn theme" on first page only transparent text(logo+start) is there in the png file.. gives it kind of glow effect when clicked.. P.S. - and the taskbar stretches below the menu logo so no need to worry about that..