Thermostat app - dial interface with flat icons to show weather forecasts, realpixel buttons
UI wheel and buttons properly termed constraint buttons. Wherever an intrinsic scale is present you can be sure constraint buttons are in the mix. Further more the circle or wheel design offers economy of design
Midi Fighter Pro. A fully featured midi controller with fast arcade buttons from Japanese video game machines. $299.99
beat mashing perfection + old school arcade buttons
35 Resizable Web Buttons
Cool Web Buttons | MaxVectors
Button/Magic - 7 Unique Web Buttons
Social Media icons Social Networking Icons - Modern circles web buttons Blog buttons - website icons. $10.00, via Etsy.