Flying Meat
FlySketch
Download FlySketch Free download, version 1.7.1
Requires Mac OS X 10.6 or later.

The Latest:
Take full screen shots via cmd-shift-5, improvements for the services menu, and bug fixes. Read all about it in the release notes.
Drawing tools for apps that don't
Some apps just can't draw. Let FlySketch do it for them.
Highlight anything
Capture a web page and highlight important bits. Send it off in an email.
Fun interface
FlySketch has a fun and easy to use interface- everything is there at the (control-)click of a button or in the palettes.
Drag and drop
Drop pictures into FlySketch. Artify. Drag your creation out.
Flexible workflow
Add a folder, application, or script to FlySketch's workflow. Pass your drawing along at the click of a button.
Hot key
Zam- make FlySketch appear at the click of a button. Poof- and make it go away.
Exporting
PDF, PNG, TIFF, and JPEG.
Tablet support
Make fancy doodles with pressure sensitive drawing from your tablet. Be creative.
Align right
Use special tools to align graphics in the canvas to top, bottom, middle, whatever.
Drop shadows
Apply dynamic shadows to your graphics. Blur and offset controls are at your disposal.
screenshots:

FlySketch window.

Highlight and capture
(QuickTime 7 Movie)

Lines n' stuff.

Doodle and drop
to MS Word.
How it works
When called upon, FlySketch will show its main drawing window above all other windows in the system. Change the transparency of the canvas, and you can trace, draw over, highlight, and capture just about anything that shows up behind FlySketch.

Workflow
Open up FlySketch's workflow folder to drop in aliases of applications or folders, and they show up in the workflow menu. Send your creations to your desktop, or Adobe Photoshop, Microsoft Entourage, or even a custom script.

It's easy
Try out FlySketch for a week, and we promise you'll think of more ways to use it. For creating documentation on your new product or just goofing around with the freehand tool, FlySketch fills a need for just about everyone.