If you remember last week was the TweakWeek in which the first tweak released was SBVolume. Well, this is a same kinda tweak and will allow you to control your screen brightness right from your SpringBoard.

After having a look of screenshot you have realized that the brightness icon is snatched by the MAC brightness icon.

To have this tweak on your iDevice search SBBrightness and it will be brought up (It is from the BigBoss repository so no need to add any repo.)