Here's a bird I don't/won't see in my region of the country. It's a mountain blue bird, seen west of the Rockies. Its song is similar to that of the Eastern blue bird; here's a link for the Cornell Ornithology site, where you can read about it and hear its song.
This morning when I was walking I heard a thrush. I don't know if it was a hermit thrush or a wood thrush, I was too far away to be able to distinguish the song - but it was wonderful to know that they are back for the summer. Here's a link to a post I wrote last summer about thrushes and it has a wonderful radio spot about the songs of thrushes.