Twitter is excellent for crowdsourcing, networking, and finding R-related resources. I highly recommend following these people in the R community:
R Ladies is a working group that promotes diversity in the #rstats community via meetups, mentorship, and global collaboration. There are over 90 groups worldwide. We have our own R Ladies group here at Vanderbilt. For updates and future meetups, follow them on Twitter and Meetup.
Why R?
R is a powerful, open source (free) programming language primarily used for statistical analysis and visualization. It is the second most popular language in data science.
Use these databases to export data in tidy, tabulated format (.csv, .xlsx).
Databases:
Miscellaneous datasets: