Popular stencils
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.
iPhone / Color Stencil
All new elements for iOS7 flat style. You can change colors to fit your requirements. It's fresh, cool and yet useful!
Tabs
Tabs stencil from the Design Stencil kit in the Yahoo! Design Pattern Library.
Touchscreen Hand Gestures
A collection of drawn hands for documenting touchscreen interactions. Includes point, tap, pinch, spread, drag.
Web Form Elements
Edward Anastas has put together a handy stencil composed of often-used elements in HTML and web page forms: radio buttons, checkboxes, combo boxes, entry fields and text areas. Nice looking and Aqua, to boot.
Pretty Urban Building Icons
A collection of icons of urban buildings
Responsive Website Wireframe Kit
Rapid Wireframing for Desktop, Tablet and Phones. Our massive wireframe library has 30 pages of content blocks, website elements, icons, wireframe examples and templates. Every single component comes in three sizes to quickly create wireframes showing desktop, tablet and phone layouts. The templates can also be used to...more
Web Detail Flowchart
The page title, page file name and page description area labels are editable. I added an example of how I use this stencil. Feel free to use as you like though.
OS logos
A collection of OS/hardware logos, including Sun, HP, Linux, Red Hat, FreeBSD, Windows, Debian, Darwin, IBM, and VMware.