Double click

Rebol interfaces can detect the double click of a mouse, it's the eighth event of a face, look a this example:

view center-face   layout [
bx: box "double-click me ! " green feel [
    engage: func [f a e] [
        if e/8   [
            bx/color: random 255.255.255
            show f
        ]
    ] ; engage
      ]
]