Illuminating Statistical Analysis Using Scenarios and Simulations

This looks like an interesting textbook for an introductory statistics course. I did not see a code repository associated with the book though.

Analyzing big data with Revolution R Enterprise

A short and yet clear introduction here.

Useful Julia resources

This is a list of Julia resources for statistics.

R, Python, and Julia

Good posting and lots of excellent comments here!

Free statistics text

OpenIntro.org provides a free statistical textbook, along with data sets and supplementary materials.

Ipsur.org is another one.