A userscript to change the colors to a more familiar blue;
http://emiri.dreamwidth.org/8232.html
And someone's edited/reworked version;
http://rainfall.dreamwidth.org/57185.html

Another userscript that changes the colors/logo (titled "Muted");
http://vigils.dreamwidth.org/7369.html

Yet another, but this one just does some minor changes from the others without messing with the colors/logos;
http://userstyles.org/styles/58319/simple-tropospherical-tweaks-for-dreamwidth

A greasmonkey script that lets you know what comments are new;
http://pw201.livejournal.com/54000.html

It's not as noticeable as the yellow button, but I'm looking at the coding now to see how hard it would be to make the link color brighter/more noticeable.
ETA: Yeah, okay, I don't know enough to do this, I'm going to ask the maker if it's possible.