Web Site Validators

Netscape's Web Site Validator

SiteInspector inspects URLs for Html Validity, Load Time, Browser Compatibility, Links, etc.

W3C Html Validator

Online Graphics Tools

Cool Archive's Logo Generator
Cool Archive's Button Maker
myImager.com from the people at Cool Archive is by far, in my opinion, the best online graphics tool on the internet.  It can do tons of things with any image you have.  Check it out!
CoolText.com
NetStudio

Graphics Programs

MapThis
A great Image maping tool!  (If you don't know what an Image Map is, it is an image that has serveral different links embedded in the image.)

Html Editors

Arachnophilia
A very good Html Editor, Arachnophilia
Notetab Lite
Cute HTML
Code Edit
Stone's WebWriter 2
Html Constellation
Web O Rama
xSite
(xSite requires IE4 to use certain feartures)
SiteAid