Ran across an article here: 13,000+ Free Icons for Web and Desktop Developmentwith some links to free icon sets. They may come in handy at some point. The article shows the icon listings, but here are just the links:

ASP.NET Icons 
390 icons, 16x16, GIF
http://www.freeiconsdownload.com/Free_Downloads.asp?id=63

Acxialis – Web Mini, Part 1
267 icons, 16x16, PNG, GIF or ICO
http://www.axialis.com/free/icons/

Diagona
400 icons, 16x16 and 10x10, PNG
http://p.yusukekamiyamane.com/

FamFamFam – Silk Icons
1000 icons, 16x16, PNG
http://www.famfamfam.com/lab/icons/silk/

FatCow - Farm Fresh Web Icons
1400 icons, 16x16 and 32x32, PNG
http://www.fatcow.com/free-icons/

Fugue Icons
6000+ icons, 16x16, PNG
http://p.yusukekamiyamane.com/

Gallery 2 Icons
77 icons, 20x16, GIF
http://paularmstrongdesigns.com/projects/gallery-2-icons/

LED Icons Set
500+ icons, 16x16, PNG
http://led24.de/

Mini Pixel Icons
320 icons, 14x14, GIF
http://icondock.com/free/mini-pixel-icons

SplashyIcons
483 icons, 16x16, PNG
http://splashyfish.com/icons/

Tango Icon Library
645 icons, 16x16, 22x22, 32x32, PNG
http://tango.freedesktop.org/Tango_Icon_Library

TwoTiny + Expansion Pack
121 icons, 16x16, GIF
http://code.google.com/p/twotiny/

Vaga
60 icons, 16x16, PNG
http://www.tenbytwenty.com/products/icon-sets/vaga

Free Web Design Icons Set
310 icons, 16x16, PNG
http://semlabs.co.uk/journal/free-web-design-icon-set

Xiao Icon
72 icons, 16x16, PNG
http://www.ineversay.com/my-works/xiao-icon.html