OpenGrok is a tool for indexing source repositories and making them easily browsable via the web. (It is also useful as a non-web-based developer tool, but this isn't relevant here.) Fisheyeis a commercial product from Atlassian that (as of February 2008) we have a demo license for and are likely to be purchasing for ongoing use.
Links to these tools are available from the isda-maven1 front page, here.
If you wish to make your repository available via Fisheye and/or OpenGrok service, drop a note to isda-ops. Currently, we are not support access control with Fisheye. (This is waiting on authentication integration.)
This server also contains a maven repository and Artifactory installation, both of which are undocumented as of this writing.