BlueSky Statistics for R

[BlueSky Statistics is a] Fully featured Statistics application and development framework built on the open source R project

Basically it makes the first 80% of the stuff that you want to do with R very easy.

The very cool part is that you get the R output so it is another great way to learn R itself.

R and S-PLUS

R is a programming language and software environment for statistical computing and graphics.

R is an implementation of the S programming language combined with lexical scoping semantics inspired by Scheme.

S is a statistical programming language developed primarily by John Chambers and (in earlier versions) Rick Becker and Allan Wilks of Bell Laboratories.

S-PLUS is a commercial implementation of the S programming language sold by TIBCO Software Inc.