Fonts are one of those things that you work with everyday but don't truely appreciate until you start running into some bad fonts.  Courier New, for example, has these casual and consistent curves that enhances readability without poking your eyeballs.

Because I have a font-fetish, I hate programming in ugly jagged fonts.  Unfortunately, there aren't many fonts designed with programmers in mind.  These days, I use 12 point Courier New font on my XP running at 1600×1200 with ClearType.  Now even spagetti code looks great.  I am not completely happy, of course, because fonts for programmers need to be more compact vertically so I can see more lines of source code at one time.  At one point, I even designed my own called Codex but they didn't scale nor print too well.  Amatur Fontographer!

I came across a new font today called Anonymous, but its got some really annoying curves.  I thought I would mention it just in case someone has different taste than I do.  What I would really kill for is a professionally designed font designed for programmers.