The Teen Titans theme song was great.

[youtube]https://www.youtube.com/watch?v=QWaWvQuIVMI[/youtube]

You know what, I just have to post the full version.
[youtube]https://www.youtube.com/watch?v=xhhOMceBJv8[/youtube]

Now that that's done, I also quite liked the TMNT theme.

[youtube]https://www.youtube.com/watch?v=fhALhLSWx6I[/youtube]

And this one was pretty good too.
[youtube]https://www.youtube.com/watch?v=dSA4NrnXT4s[/youtube]