The following is an example that demonstrates unexpected behavior of .lastUnit on FF 3.6 and Chrome 6.0. IE8 does not appear to be affected. I have not tried other browsers yet.
Removing clear: both from .lastUnit:after appears to fix the issue, but I am not sure if this created other problems.
do you have an example online somewhere? I think github is stripping some of the code.
Yep, sorry about that. Here it is: http://www.ypass.net/lastUnit.htm