The Brush: http://sta.sh/016j7nyhovjq
How to Install: Open it in PS, Edit, define brush preset. Go in to brush settings, other dynamics and enable both the opacity and flow jitter to pen pressure. Spacing 10%.
GIMP, you'd probably have to Google for that one, I don't know. :(
Or you can download it and a bunch of other cool brushes here: http://sugarpoultry.deviantart.com/ar...
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