Font or not, I wouldn't encourage it.
Imagine code where you had variables l (lower-case L), I (upper-case i) and O (upper-case o). And you had lines like this:
a = 1;
b = l;
c = I;
d = 0;
e = O;
You would have to have eagle eyes and good concentration not to get confused by that sort of stuff.
And you don't necessarily control the sort of font that other people who view your code might use.