Iconoir - A diverse and open-source library with 900+ icons
IconShock - Over 2 million free icons in 400+ icon sets over 30 styles
Flat Icons - 20,000 unique, customizable icons with free lifetime updates
Nucleo - Commercial vector icons and accompanying apps to manage and customize them.
Blobmaker - Create organic svg shapes in just a few seconds
Glyphish Icons: Watchkit - Watchkit version of the famous & fabulous Glyphish icon set!