Scripts and small programs I have used regularly in the past. Most of the links are to code listings that can be cut and pasted into a text editor.

Bash script that generates web pages from source code files. Used to generate the web pages for the three utilities given here.
Bash script to gives the word read access to its arguments. Recurses through directories. Requires Cygwin and the file command to run on Windows.
A C program to check whether file arguments contain tabs and/or lines wider than a given width (default: 80). Output is suitable for pasting into grading reports for student projects.