NashFP's Rosalind playground. Rosalind is a project-euler-like platform for learning bioinformatics through problem solving.

"Make sure you register: allows downloading test data sets & tracking your progress. Addictive" -- John Daily

Pick your favorite problems from here: http://rosalind.info/problems/list-view/ and solve them using your functional language of choice. Contribute your solution by adding a folder named {your twitter handle}+{your language} such as:

/bryan_hunter+erlang/dna.erl

Time to play!