Developed Auto Ideas: Now What?

Dear Rich: In 2004, I drew up two sketches with written descriptions for two different automobile ideas, one of which I designed as an enhanced safety feature, and one of which I designed as an enhanced security feature. I sealed the works in an envelope, mailed them to myself, and had the envelope notarized. I have a renewed interest in learning how to go about further protecting and getting the designs in front of the appropriate department of an automotive company. There are two ways to protect your undisclosed automobile ideas: (1) as trade secrets (in which case you'll need to use NDAs when disclosing); or (2) by obtaining patents.
Design patent or utility patent? Although you're using the word "design" to describe your innovations, they don't sound like design patent material (which is reserved for the appearance of functional objects). If your innovations enhance safety or security, then they are functional and may be the subject of a utility patent. Read up on utility patents to decide whether your ideas will qualify. Keep in mind that the date of your invention -- 2004 -- is less relevant now that the new patent law will go into effect in March. And if you've made any public disclosures of your idea, that will likely kill any patent hopes. As for the notarized envelope, don't expect that to provide any protection. It's sometimes referred to as a "post office patent" or "poor man's patent." But whatever you call it, alas, it doesn't prove anything.