at least when it comes to my dogs. I got a great screen thingy where I can leave the door open for them to go in and out. They love going in and out on the days I work from home. Zoe zoomed through it the very first time. Zena after about 2 times of showing her through myself. The boys....well let's just say they are still wondering if it's going to attack them.
Must be the male gene in wanting to figure out how things work and are made. Anyway, here is what I got and I highly recommend it if you love keeping your door open and the bugs out.
http://www.bugoffscreen.com/index.shtml
http://www.bugoffscreen.com/index.shtml