I got this as a Christmas present. My ride isn't going yet, so I can't comment on using it, but it seems like it will work well. It is being marketed as the world's best blind spot mirror. My mom got it for me and was surprised I was so happy with it. She said she just got it cheap and didn't realize that I was going to get a blind spot mirror any way.
www.maxiviewmirror.com

another site I found but looks the same:
www.maxiviewmirrors.com

Both sites are advertising them at $30, but I think my mom said she got the pair for like $5. If anyone's interested, I can find out where she got them.