[Groxx]

I keep tacking RCS onto the ends of these, too :) It keeps surprising me - Mercurial passed RCS ~ last June, and Bazaar passed it in roughly June of this year. It gets a lot of usage still.

[Estragon]

I use it pretty often for casual alteration of configuration files.

[mkopinsky]

Why do you prefer it to git or hg for this use case?