Mark James (FamFamFam) created a great set of 1,022 silky-smooth 16x16 true-colour icons in PNG format, aptly named Silk Icons.
My set was fuelled by a need for a additional icons and variations in the same format. I had hoped to create more original icons in the same style however time constraints meant that majority of the 460+ icons are derivations and recompositions of the original set.
Use one of the many package managers to install, full details are available on GitHub
Download Silk Companion #1 (ZIP of PNG) (384 KB)