Rattle is a graphical interface to R. It supports basic data management tasks, as well as a number of different modeling functions. I haven’t had a chance to test it out yet since I don’t have my R installation completely up to date, but it looks promising. For all of R’s strengths, one weakness is the inconsistency of the syntax from command to command and package to package (not that commercial applications don’t have the same problem).
Also see RCommander.
