It is possible to create additional font & color schemes in NetBeans 5.0. Although the new Options dialog is still a bit buggy (e.g. preview doesn't work), we received first custom fonts & color scheme as a contribution from NetBeans community. Martin Van Tonder from South Africa sent me a zip with a scheme and he agreed with publishing it, you can download it here:Martin's Diamond font & color scheme
To install, just unzip this file into your userdir into config subdirectory. You can then change the scheme by choosing "Diamond" in fonts & colors section of new Tools | Options. Martin seems to really like green color :-)
If you have created a nice scheme yourself, why not to share it with others? It's possible now to create custom schemes for shortcuts as well!