myGrid := PasteUpMorph new openInWorld.
myGrid height: 1100;width:1100.

rnd := [(-500 to: 500) atRandom].

aRecta := RectangleMorph new.
myGrid addMorph: aRecta.
aRectb := RectangleMorph new.
myGrid addMorph: aRectb.
aRectc := RectangleMorph new.
myGrid addMorph: aRectc.
aRectd := RectangleMorph new.
myGrid addMorph: aRectd.
aRecte := RectangleMorph new.
myGrid addMorph: aRecte.
aRectf := RectangleMorph new.
myGrid addMorph: aRectf.
aRectg := RectangleMorph new.
myGrid addMorph: aRectg.
aRec := myGrid center.

[Transcript show: (Time millisecondsToRun:[
    1 to:1000 do: [:i|
        1 to: 1000 do: [:j|
            aRecta center: aRec +(rnd value@rnd value).
            aRectb center: aRec +(rnd value@rnd value).
            aRectc center: aRec +(rnd value@rnd value).
            aRectd center: aRec +(rnd value@rnd value).
            aRecte center: aRec +(rnd value@rnd value).
            aRectf center: aRec +(rnd value@rnd value).
            aRectg center: aRec +(rnd value@rnd value).
            ]]]);cr] fork.

Smalltalk garbageCollect.