Legal Wills Online

Standards that are tested wills are set by individual states. But I do not know the state that accepts a "line" will be.

Most states have strict standards for testaments, including a public officer and attestation. You should check with a qualified attorney in your area.

legalzoom.com

Yes they are. You can write a will on a napkin from a local bar, and it would be accepted by a probate court. See url below.