Recommended fixed width font for shell prompts and Eclipse
My personal favorites are the Bitstream Vera Sans Mono derivates like Menlo and DejaVu Sans Mono:



Espresso Mono doesn't have an italic face, Mensch doesn't have bold or italic faces.

Cousine and Liberation Mono are basically the same font designed by Steve Matteson. The shapes of all ASCII characters are currently identical, but Cousine was released with the Open Font License (instead of GPL v.2) for Google Web Fonts. They are metrically compatible with Courier New, but appear more like more angular versions of the Vera Sans Mono fonts. Liberation Mono currently has more glyphs (674) than Cousine (216) though.



Droid Sans Mono is another font designed by Steve Matteson. It currently has glyphs for 898 characters, but no bold or italic faces. The default line height and character width are both larger than in most monospace fonts.



Inconsolata is a monospace font with humanist features. It has slanted edges and more width variation than most monospace fonts.



PT Mono is part of the same family as PT Sans. It's lighter than most monospace fonts, and has many unique details at the ends of strokes.



Source Code Pro is a new open source font by Adobe. It has a low x-height, large line spacing, and wide slabs on the lowercase i, l, and t. It also has a two story lowercase g like Inconsolata.



If you think text looks too heavy on OS X, there's a hidden preference for selecting a lighter text rendering style.