Anonymous Pro (2009) is a family of four fixed-width fonts designed especially with coding in mind. Characters that could be mistaken for one another (O, 0, I, l, 1, etc.) have distinct shapes to make them easier to tell apart in the context of source code.

I also roll it on a barely transparent black background (just enough to see text I might be copying behind it) in a lovely shade of banana and at 12px.