Here some subroutines in fortran90. Until last year fortran was compulsory for my course of Computational Physics. From this year our faculty has chosen C as "mother tongue" for our students and therefore it is up to them to choose a language for their exercises. As far as I am concerned I think I will remain with fortran for scientific work and I am learning Java for educational purposes and for fun.
The following programs are taken from those written by one or more students of my course. The main contributors are acknowledged in green

• write time and date in output file Michiel Alsters
• root finding by bisection Chris Dams, Joris Mooij
• random numbers built-in subroutines
• code for selecting a step in a Random Walk
  uses built-in function floor and select case constructor Chris Dams