The CvsGui project is providing several high-end interface clients (WinCvs, MacCvs, gCvs) written in C++ using popular frameworks (MFC, PowerPlant, GTK+) with a scripting support via Python or TCL.
The tcl.prehiti.net applications are a collection of useful development, productivity and image manipulation tools written in tcl. The featured application is mcvs.tcl, a new graphical front-end for CVS.
CVS Chronoview is a client-side tool that presents a chronological view of the history of multiple files in a CVS repository. It does not rely on any server-side tool.