Have any of you geeks used R? I am thinking about delving into it for some basic descriptive statistics and regression analysis (for social science applications), and maybe some pretty graphs. Is R worth it? Is R "easy" to use/learn? I've used SPSS and STATA. If you haven't heard of R, maybe you'll want to check it out too. It is a freeware-GNU software environment for playing with (large amounts of) numbers and graphs.