Ten Foot Cones?

[MerakSpielman]

That's not the case.

I used the definition from the SRD:

Cone: When the character casts a spell with a cone area, the cone shoots away from the character in the direction the character designates. A cone starts as a point directly before the character, and it widens out as it goes. A cone's width at a given distance from the character equals that distance. Its far end is as wide as the effect is long.

Also, note that cones in 3.0 are defined as triangles. In 3.5 (which my drawings don't indicate) they seem to be defined as arcs - at least, according to the DMG image people posted in my "spell radii" thread. Personally, I like the 3.0 version of cones because, well, I can visualize them as being actually "cone" shaped. The ones in 3.5, while covering more area and being easier to figure out, should be called something else.