When creating ExtJS application you must be need some of cool icons, mostly the icon used in ExtJS component like in toolbar, menu, tab, treepanel, button or any other place on the component which the icon can be customized based on your need. Here I create a list of mini icons set that can be used in your ExtJS application, the icons was handpicked only for the size 16 x 16 pixels, that suit in the ExtJS default themes.
01. Free Icons Sets by Axialis
License: Creative Commons Attribution 2.5
02. Sweetie Icons by Sublink Interactive
License: Creative Commons Attribution-ShareAlike 3.0
03. Silk Icons by Famfamfam
License: Creative Commons Attribution 2.5
04. Mini Icons by Famfamfam
License: Free For Any Purpose.
05. My Web Control Icons by Marko
License: Creative Commons Public Domain
06. Sanscons by P. J Onori (somerandomdude)
License: Creative Commons Attribution-ShareAlike 3.0
07. Doctype Icons 2 by Brandspakingnew
License: Creative Commons Attribution 2.5
08. 16 x 16 Free Application Icons
License: Creative Commons Attribution-ShareAlike 3.0
09. Led Icons Set
License: Creative Commons Attribution 3.0
10. 16 x 16 Free Toolbar Icon
License: Creative Commons Attribution-ShareAlike 3.0
11. Circular Icon Set by ProThemeDesign
License: Creative Commons Attribution-ShareAlike 3.0
12. Bitcons by P. J Onori (somerandomdude)
License: Creative Commons Attribution-ShareAlike 3.0
13. Twotiny
License: Artistic License/GPL
14. Fugue Icons and Diagona Icons by Yusuke Kamiyamane
License: Creative Commons Attribution 3.0
15. Vaga Icon by Tenbytwenty
License: Royalty Free (see complete license agreement)
16. Tango Icon Library
License: Creative Commons Attribution-ShareAlike 2.5
17. Phoenity Aura by Phoenity
License: Creative Commons Attribution-ShareAlike 3.0 and LGPL
18. SpalshyFish
License: Creative Commons Attribution 3.0
19. Free Web Design Icon Set
20. Iconza
21. Chalk Work Payment
License: Royalty-Free (see detail)
22. Pixel Perfect Social Media Icon by Benjamin Reid
License: Free for personal and commercial work. No attribution required.
23. Elegant Blue Web Icons by Emre Ozcelik
License: Creative Commons
24. Free Fresh Farm Web Icons by Samantha Evans
License: Creative Commons Attribution 3.0