The site to join is http://www.socialup.net/
Install firefox and download imacros plugin.
Download imacros scripts at http://www.socialup.net/socialup.iim
Login to digg.com using your digg username and password.
Login to http://www.socialup.net ,and click surf now button.
In firefox run imacros script socialup.iim and set repeat macro 100 ,you can go to sleep now.
use this macro you can get credits automatically.
You may earn 50 or more credits an hour,then add your digg.com urls in "Site Maintenance" ares , allocate credit for it,you can get diggs automatically.
This is a great technique for people who only want to spend 10 minutes a day can get more diggs and visitors to your sites.just enjoy it.