The Online Generators list seems to have everything you could every want out of an online generator.

Highlights:

ASCII Art:
http://www.glassgiant.com/ascii/

Color Blender:
http://www.colorblender.com/

Gradient Creator:
http://tools.dynamicdrive.com/gradient/

Favicon Creator:
http://www.dynamicdrive.com/favicon/

A couple I created:

Quick Thumbnail:
http://quickthumbnail.com/

Make Password:
http://www.maord.com/

Link:
http://www.smashingmagazine.com/…/online-generators/

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