Flymake Cursor
Emacs Flymake Cursor is a plugin for Emacs that hooks into Emacs Flymake to display details in the message area for the error under the cursor, which is helpful if you're running Emacs in a terminal and don't have mouse support.
Originally by persons unknown, my fork on GitHub is based on the version on EmacsWiki and adds the following features:
Customizable delay before the error appears in the minibuffer.
Customizable number of errors to display in the minibuffer.
Does not overwrite the minibuffer if it's currently in use for user input.
Updates message area more consistently as flymake changes state.
Turns off when flymake-mode is turned off.
Now operates as a minor-mode of its own so you can turn on and off directly.
Requires flymake, ensuring a clean byte-compile.
There's also tighter integration with my fork of Emacs Flymake although it also works fine with the standard version of Emacs Flymake bunded with Emacs.
You can find more on my GitHub page for Flymake Cursor.
Recent blog entries for Flymake Cursor
I don't appear to have written any blog entries about this project yet.