Although Smalltalk environments traditionally use variable width
fonts, people are sometimes motivated to switch to a monospaced font.
When I look at the reasons, I think it is mostly because the variable
width fonts we have were not specifically designed for showing code.

As an experiment, I made a set of proportional fonts that incorporate
the design features we expect in a programming font. There are both
bitmap and vector fonts.

Note especially that the spacing is adjusted so you don't have to use
tabs for indentation. This means you can write code that looks good
with either a monospaced or proportional font.

All the fonts are release to the public domain (via the Unlicense) and
can be found at http://code.google.com/p/i3project/wiki/Fonts.