There are a few options that I can remember that may fit the bill, here
1 Fit an old CD tray motor from a computer under the seat- when the drawer goes in, the plate goes up....there's a how to on the forum somewhere.
2 A friend of mine fitted the cable from a 3 speed bicycle, from the bars, under the seat and down to the plate. Pull the cable and the plate will lift. There's no evidence if you fit it right.........
3 I've heard of someone using an old electric motor from a car electric aerial.

But for me, I use a whole can of clear spray on the plate, lay it down flat so it sets evenly. About 10 coats, and when light hits it, you get a silver square on the camera.
Sometimes simple is better.....................

 

I thought they tried this on Mythbusters and showed that it didn't work. Maybe they didn't spray enough coats on it.

 

"Clearly" they didn't use the right stuff.
Use a whole can on the plate and it also distorts the lettering.....

I've also heard that window film is quite good, but haven't tried it (yet)

 

i was driving my big truck in chicago picking up a steel coil at wheaton steel well there is hundreds of them cameras in chicago i could see them taking pictures of the top of the flat bed i guess there not programed to take a pic of a tractor trailer. but they dont give enough time for us to stop anyway in that short of a time. but yeh its big brother taking us to the cleaners

 

I still think it's better to hit the cameras themselves.

Old tyre and a can of petrol, once it becomes too costly to replace the cameras they'll get rid of them

We also get 'average speed cameras' at roadworks, logs your speed at two locations and works out your average speed, infuriating when there's no traffic, but you've still got to crawl along

 

Or go like hell for half the distance, then stop for a p!ss or break out the thermos for a cuppa before carrying on

Where I live we don't even have traffic lights, let alone cameras. There's only three roundabouts in the main town 22km from my place and when the put them in it was chaos. I don't think some of the old timers had hardly ever left town. They even put a write up in the paper on how to use them properly.

There's a mobile speed camera which rotates through 4 districts for a week at a time but it sticks out like dogs' *****. Biggest problem is the ever increasing numbers of hand held devices and plain cars. The cat and mouse games continue eh?

 

+1 on hating speed cameras. Have never gotten hit on my bike, but have in my car.

Here is aphoto of me in the front - its not a speed camera, but it IS Pretty funny

 

Cool pic, nate.

I was on the highway a few years back and came across one of those signs that shows the limit and your current speed. I wanted to see a high number on it (because I'm an idiot), so I doubled back to pass it again going a bit faster. Turns out that they won't display your speed after a certain point.
I don't know if some of them can't pick up a signal properly at that high of speed or if the cops refuse to give people the satisfaction of seeing triple digits but it would just flash these weird lines on the screen as I passed.

I wanted it to look more like this one below, but it's a lie!! lol...