I recently demo'ed my phylogenetic nomenclature app, Names on Nodes, at the iEvoBio conference in Portland, Oregon. This caused me to actually get up off my butt and launch an alpha version of it: Names on Nodes: Standalone Version. (Flash Player 10.1 is required.)
I need to add some easier ways to get in and start playing with it, but for now you can click on "Newick" and enter a Newick tree string or try opening a NexML file (e.g., from TreeBase; here's a nice one). You can then click on the "+" button in the "Names" panel to start adding phylogenetically-defined names. You can save your work as MathML files.
There are a lot of issues left to resolve, and feel free to make feature requests.
I'm also working on a Java implementation, which won't have a GUI but will be better able to handle large datasets.
