Best monospaced font ever is Consolas from Microsoft. It’s installed with the Office 2007/03 Compatibility Pack and with Office 2007. So you’ll need an instance of Windows with Office 2003/07 to get this font, it also comes with Visual Studio I think (as that is what this font was designed for, people looking at code all day)..
I also installed this font in Xubuntu for use as my terminal font. Doesnt look quite as nice on Linux/Xubuntu as it does on Windows, but it was still the one I liked the most for my terminal.
For TrueType fonts, make a directory and copy the .ttf files:
Rebuild the font cache thing:
fc-cache -f -v