Actually, Chimera's tool for viewing trajectories, MD Movie, does "RMSD analysis" but that's somewhat different; it plots all-frame-by-all-frame RMSDs in a grid where each value is an RMSD over all specified atoms. Basically, it's for comparing whole frames (MD timepoints, snapshots of the whole structure) to one another, not for evaluating local conformational variability.
Eric Pettersen
UCSF Computer Graphics Lab