Very cool new app named Layers. It produces a screenshot on OS X as a layered Photoshop document where every window is on a separate layer.
It’s currently available at a promotional price of $15.
Via MacMerc.comLayers: Screen forensics
Capture your displays as a Photoshop layered image
Don’t waste time capturing each window separately, importing them in your favorite PSD editor, naming the layers, positioning the images, etc.
Do it with Layers in no time! Press the capture hotkey or customize your capture in the inspector. You’ll obtain a full fledged PSD file with one layer per window, including menu and desktop icons, dock and menubar.