Inspired by the "internationalize your menubar clock date" hack, here's the "put the date right in your menubar" hack.
It effectively changes the "show the day of the week" option for the menubar clock to "show the day of the week and date". For example, mine now says "Mon Nov 26 2001 5:40 AM"
Here's how to do it ... (if you're cautious, back up Clock.menu or just Clock)
cd /System/Library/CoreServices/Menu\ Extras/Clock.menu/Contents/MacOS/
sudo perl -p -i -e "s/%a /%x /" Clock
sudo perl -p -i -e "s/%x /%a /" ClockThis is tested to work under 10.1.1. It should work fine on other versions, but no guarantees.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20011126090439402