I have found it very difficult to see which posts I have read (especially if the monitor is in a bright room/office) - a different colour would be beneficial.
And the second suggestion, would it be possible to trace, monitor or log the posts visited during a given session e.g. I read a brilliantlly well writtten and articulate article about an op-amp offsetting a diodes 0.6V forward drop (I think in a rectifier circuit) can't remember anything else about the article and the search facility hasn't found it