Scribing

The back side of my wornout #11 blades.

What can I say... I'm cheap. 

Ok ok, I also have one of those pick sets I bought for my automotive toolbox.
It was cheap - one handle, four different shaped picks, in a plastic pouch.

i started out with a sowing need,cut in half and the inserted into an exacto knife handle,it served it's purpose until i found the Testors scriber that i wanted

My dentist has unloaded a bunch of dental tools on me. Some he was just going to pitch anyway. Don't be afraid to ask. Some of them work just as good as the expensive ones.

In addition to a purpose-built scribing tool, I also use a sewing needle chucked in a pin vise.

You could also try looking for second-hand tools from unlikely sources...

I've heard lots of people have success with dental tools, but I haven't tried that route.

And then in my last job, we used a few tiny (~1/32") end mills, but being so small that they broke pretty easily.  I've taken a couple of the broken ones home and tried using them with varying success... they're very sensitive to direction/angle of use.  So if you can find a machinist, you may want to ask if he's got any small broken end mills (it may help if he works at or has done work for a scientific company or a university... I think they're more likely to come up with odd-ball stuff that needs cutters that small).

Hobby Lobby has cheap scribing tools, around $4 or so.

Check out Swanny's Scribing tips. He uses a scribing tool he bought for six bucks. You should also check out Harbor Freight or Princess Auto (or some other "discount" tool store) for a set of cheapo dental tools. I picked up a pack of them for less than ten dollars. Now my kid's teeth are in great shape!

Nah, just kidding, I do find them handy for rescribing panels lines etc.