Everybody's seen redirection in bash commands, that's pretty common, but bash also allows you to define redirections when you define functions. This causes the redirections to be evaluated/executed whenever the function is called.
In diff tool speak, a visual diff tool is a GUI application. Meld is such a tool: a tool for displaying differences between files (and directories) and also for merging the differences. Meld is programmed in Python.
Like other word processes, OpenOffice.org Writer makes creating tables of contents (ToCs) quick and easy. Unfortunately, it also works with unaesthetic defaults and allows you to make choices that complicate your work flow rather than improving it.