Thankfully somebody over at http://www.kuro5hin.org/story/2004/12/6/11739/5249 has made up a little discussion of programming fonts, and he's put together a comprehensive list of monospaced TrueType fonts out there. Included are Courier and Courier New, along with the popular-but-difficult-to-find Andale Mono. He also found a whole slew of others. If you want to see all the fonts, grouped by his personal preference, check out http://www.lowing.org/fonts/allfonts.htm.
His top choice does look quite nice. I'm gonna have to install it.