OpenGrok is a fast and usable source code search and cross reference engine. It helps you search, cross-reference, and navigate your source tree. It can understand various program file formats and version control histories like Mercurial, Bazaar, Git, ClearCase, Perforce, SCCS, RCS, CVS, or Subversion. In other words, it lets you grok (profoundly understand) the source.
sccs2svn converts a SCCS repository into a Subversion repository. The script visits a directory tree with SCCS repositories. It then sorts the SCCS deltas by time and applies them to a Subversion repository. The script attempts to transform some SCCS keywords to Subversion keywords.