eTiny (OpenERP’s web server) shows default header images and style that might not really suit your needs.
Being GPL, you can modify that at will, but you have to know how.
Although it’s probably not the best way to do it, you can easily alter the existing images to show something a little different.
This is all done (on a Debian/Ubuntu server) by changing the files in /usr/lib/python2.4/site-packages/eTiny-1.[0.1.1]-py2.4.egg/tinyerp/static (the part between brackets may vary) to suit your tastes.
The important files are
So just make a backup, open them, change them and put them back in to get a very light (but refreshing change).