In the spirit of the Joe the Plumber political fad, here's my 10-minute halloween costume: a road named Share. Get it?

Step 1: Gather Your Materials and Tools

Materials are really simple:
2 cans spray paint: 1 each of black and yellow
2 ~3' x 4' pieces of plastic. rigid plastic campaign signs are appropriate and would work, but you could also probably make due with cardboard
1 worn-out bike tire
a couple feet of duct tape
a name-tag

Likewise on tools:
surface on which you don't mind getting spray paint
a pen, for writing on aforementioned name-tag
a pair of scissors

Step 2: Cut Out Your Road, Lines, and Straps

Cut a comfortable height and width from the plastic for both sides of your body. Keep in mind what you'll be doing while wearing the costume; for me, bicycling in this outfit meant I wanted something a bit smaller and more maneuverable. In retrospect, a smaller width than what I did would have been much less uncomfortable...

On the stripes, cut at least one extra: duct tape is a fickle lover:)

Step 3: Spray Paint Away

I made the road stripes by sticking the duct tape to a fairly-clean surface and spraying it until I saw all yellow and no gray. The plastic for the road then got sprayed solid black. Pretty straightforward!

Step 4: Make Your Harness

I tied knots in chunks of an old bike tire after placing it in a hole through both sides of the sign for a minimalistic harness. Definitely room to make this more comfortable for your version!

Step 5: Add Your Nametag

Here's an image of the nametag I used. Obviously, you can make a groovier version. I printed on normal paper and attached to the road with hot glue.

Step 6: Make a Better Version

I could have enhanced this specific theme by:
-adding black face paint with yellow lines continuing
-sporting black pants w/ yellow as well
-making the road plastic more comfortable. biking with this costume was an experience in chafing, to say the least...

As for variations, have at it. Roadkill comes to mind (below photo from the "your mama." blog), but there are plenty of other name-occupation (name-thing?) possibilities that you and at least one other person will find entertaining:)