[Simple Particle Script] 1000L to whomever can help me!

Okay, I have a idea and I need help with the scripting.

It shouldn't be very advances

but, I want to wear an object and when I press W A S D or UP DOWN LEFT RIGHT the object will rez a prim behind me and then disappear within a second.

I want it to continue rezzing whenever one of these keys are pressed
and stop rezzing when it is not pressed

Particle Generator script? or something that I can set to just rez a image or prim directly behind the attached object on the avatar.

any who.. any help will be greatly appreciated
and will be happy to donate lindens to whomever can help!


http://youtube.com/watch?v=0i8iWqFJE5g
EXAMPLE

Haha, just made exactly that the other day...lol