I used to switch fonts between different ones all the time. About a year ago, I found Envy Code R. I haven't switched since. Easy to read, easy to tell the difference between zero and O, paren and curly brace, etc...<p><a href="http://damieng.com/blog/2008/05/26/envy-code-r-preview-7-coding-font-released" rel="nofollow">http://damieng.com/blog/2008/05/26/envy-code-r-preview-7-cod...</a>