Migrate project from RCS to git?

OK, after a little tinkering, I found it was trivial to convert RCS to CVS. The files are in the same format, so it's simply a matter of moving the files into an existing CVS root. This assumes you have access to the RCS files.

# Create CVS root dir. You only need to do this once.
mkdir $HOME/cvs/
cd $HOME/cvs/
cvs init

# Import a repository from RCS to CVS
cp -a _projectname_/RCS $HOME/cvs/_projectname_

Here I elaborate on Edward Falk's answer by trivially converting from RCS to CVS, then convert CVS to Git. This example uses git-cvsimport to convert from CVS to Git, but any other CVS to Git conversion method should work.

mkdir $HOME/mydir/  # Any directory name will do.
cd $HOME/mydir/
cvs -d $HOME/mydir/ init

# Trivially import an RCS project into CVS.
cp -a /path/to/_projectname_/RCS $HOME/mydir/_projectname_

# Convert the CVS project to Git.
git cvsimport -d $HOME/mydir/ -C mynewgitrepository _projectname_

See Interfaces, frontends, and tools page on Git Wiki, in "Tools", "Interaction with other Revision Control Systems", "Other". There you would find a description and a link to rcs-fast-export (gitweb) Ruby script by Giuseppe "Oblomov" Bilotta.

(Web search would find also Ohloh page and announcement for mentioned project).