Icons

⌛ This hasn't been updated for a while, so could be outdated (particularly if it's about something that evolves constantly, such as software or research).

Web

Small and usually clear icons, roughly sorted from most icons and easiest terms, to fewest icons and annoying terms.

• Famfamfam, a wide selection of icons: silk, mini, mint, and also flags.

License: cc-by

• sweetie

License: cc-by-sa

• (not sure about the name)

License: cc-by

• BrandSpankingNew Mini Icons 2, geared towards text editing, CMS, and some social webbing.

License: cc-by-sa

• Some smaller sets from BrandSpankingNew: Mini Icons Pack 1, Doc Type Icons 1 and Doctype Icons 2.

License: Unsure, but seems freely usable

• Minimalist Pixel Icon Set - small, clear, sort of random subjects

License: cc-by-sa

• Bitcons

License: cc-sa

• Twotone white-on-single-color, fairly clean

License: Unsure, but seems freely usable

• Bitcons and Bitcons+, fairly clear red-and-white icons, various topics. Also Sanscons, the same set white-on-transparent so you can use them with any background using some CSS-fu.

License: Unsure, but apparentrly freely usable and 'be generous with the linkage'

• Drunkey love iconset is mostly CMS-focused, and has flags.

License: Unsure, but freely usable and 'just don't pass them off as your own'

• mIcons / Markup icons, some clean shaded monochrome icons.

License: unsure

• Tiny Little Icons / Milk and Green, 21 small, clean icons.

License: unsure, but looks freely usable

• 'My Web Control Icons', ten basic icons apparently made for a config utility

License: Public domain

• Feed Icons just that well known feed icon -- but in a lot of colors:P

(see also [1], [2], [3])

• graphicPUSH Blog Icon Pack

License: 10 core icons for free, the rest for $12

• Mini Pixel Icons. Web-geared.

License: Link back, or pay $30

Apps / Desktop

Larger, shinier, perspectivier. Usable for web uses if you're into that sort of thing.

• Tango Desktop Project (cc)
  • its gallery
  • Art Libre set (for graphal apps)

• http://phytonix.deviantart.com/art/Ricebowl-22605468 RiceBowl

License: LGPL

• Genato

License: Unsure, but only minor conditions

• Dropline Etiquette, Dropline Neu, Dropline Nuovo!, Yasis

License: GPL

• kNeu

License: GPL

• nuoveXT, NeonX

License: GPL

• Nuvola

License: LGPL

'Greyscale' License: cc-by

Other / unsorted

Useful lists (that helped):

• http://www.maxpower.ca/free-icons/2006/03/05/

• http://iconlibrary.iconshock.com/icons/100-free-web-elements-sets/

Animated 'busy' icons:

• http://www.andrewdavidson.com/articles/spinning-wait-icons/

Icons from many sites, to help you brainstorm creating your own:

• http://www.intersmash.com/300images/
• http://www.simplebits.com/notebook/2004/08/23/anatomy.html

There are also a good number of stock icon sites where you can buy icons. For example:

• http://www.iconbuffet.com/
• http://www.iconexperience.com/

Unsorted

• http://dezignus.com/