I've been working on a new addon for the last couple of weeks called DungeonTimer. Basically it tracks your time on 5-man heroic instances.
I know there is another addon called DungeonSpeedRunner that does something similar, but it is limited by the way it is coded to only working with Random 5-man groups and it won't work with non-Random runs.
Sure, that distinction may not matter to everyone but it bugged me since I do sometimes run specific instances for achievements and stuff and wanted those tracked too.
I will be publishing betas through curse and alpha (developer) versions will be on curseforge.
Note: v1.0-beta1 has a few issues so if you're going to try it out, I suggest you look at something more recent.