Question

Does anyone know of a way to create horizontal rules within a <textarea> without using a background image?

CSS3 would be fine. I can bodge an image fallback for IE if necessary.

Example:

Answer 1

You can do this using linear gradients:

.notes {
    background-attachment: local;
    background-image:
        linear-gradient(to right, white 10px, transparent 10px),
        linear-gradient(to left, white 10px, transparent 10px),
        repeating-linear-gradient(white, white 30px, #ccc 30px, #ccc 31px, white 31px);
    line-height: 31px;
    padding: 8px 10px;
}

<textarea class="notes"></textarea>

JSFiddle Version