I discovered more about mashups from looking at the Library Trading Cards on Flickr and then attempting to make my own using Big Huge Labs. I did make the card but had some trouble trying to post it to the blog. Here is the link:
I get how mashups are really useful because you can use a variety of different applications and build them on top of each other, but I got frustrated because I had to be redirected several times and sign in using various usernames that mostly I had forgotten. Then when I tried to post the card on my blog it told me I couldn't connect but didn't say why. Maybe I will try again later.