I hang old CDs in our fruit trees to scare the birds off. Doesn't work, but the sun glinting off them is quite a nice effect.

Don't have any trees ;)

Hang them from the mast to keep the seagulls away from your shark n tatties.

Throwing in a CD folder full of random software CDs and a lot of different versions of Windows as well.

Trademe it. 

Pending pickup

these must have cost you a fortune back in the day! glad someone has found use for them.

as mentioned a few times, i use discs by the clothesline to shoo birds away, though i'm not sure they work.

nitro:

 

these must have cost you a fortune back in the day! 

 

I was thinking the same thing, they would have been 20K+ new

nitro:

 

as mentioned a few times, i use discs by the clothesline to shoo birds away, though i'm not sure they work.

 

Swap them out for some Celine Dion.

That'll scare anything away.