I have no idea if this works, and have no relationship with The Wildbird Store, but this suggestion for a woodpecker deterrent arrived in my email this evening. Could be worth a try to those having flickers pounding in their eaves!

Pat Grainger
Port Townsend
paq at olypen.com

The Best Woodpecker Deterrent Ever!

The Attack Spider is Here
Just in time for Woodpecker Mating Madness!

This little sound activated spider can be tucked into the eves of your house where the flickers and woodpeckers like to drum. When the drumming starts, the spider drops out of the eves and scares the beejeezsus (yes, that is the technical term!) out of the birds, without harming them! This is a safe and effective way to keep the woodpeckers from pounding on your home. Click on the link below to see an in store demo of the Attack Spider!
Only $17.99 each.
http://www.youtube.com/watch?v=-z0U7IFyw5g