My dear friend from high school, with whom I share a love of animals, just told me about the Rainbow Bridge, so I'm putting it here. I went to this church for a couple of years that seems to have gotten its inspiration from this poem, and from this video in particular. It has a big Jesus and a rainbow on the wall over by 35W near the University of Minnesota and it's called "Lovepower." The people are very tender and older and inspired by the 60's, I believe.
I ended up not going there, just dropping in to visit once in a while, because they were a little wacko and had some weird problem relating to young people, and just played very uninspired, twangy music that I couldn't stand. But they helped me during a difficult time, and I was touched by their rainbows and their love of pets and their "pennies from heaven."
I like the poem because it suggests that animals came from God and therefore will return to God, and you will be with them too if you are going to heaven.