Popular stencils
Braces
Braces in different thickness and size.
AIGA Symbol Signs
Used at airports and transportation hubs, the AIGA symbol signs are a joint effort between AIGA and the U.S. Department of Transportation. Especially nifty for making maps of floor layouts for public display.
Vmware Icon Library
Diagram and Icon Library
UX People Builder (Guys)
Create your own stylized people for use as personas, icons, individuals, or groups on your charts, diagrams, and illustrations of information, ideas, and concepts. Use in conjunction with UX People Builder (Gals) stencil. Optimal for information architecture, interaction design, and user experience projects.
Round Arrows
A small collection of round arrows to create a circle of arrows. Each arrow can have a different color.
Tabs
Tabs stencil from the Design Stencil kit in the Yahoo! Design Pattern Library.
Rounded Numbers
Why clutter up your diagrams with a lot of text when the most used way of annotating diagrams is by using a number or a letter inside a circle? Very useful when needing to annotate diagrams, drawings, or photographs.
Bantik UML
Because UML doesn't have to be black and white... Version 2 turns the 'object' object into a table, making adding an attribute, method, or private method as simple as command-enter.
Annotations
A set of annotations for photographs and diagrams inspired by the excellent annotations available in Little Snapper from RealMac Software.