I was aware of the dot-dec-ip address immunity. That's the reason why some pesky sites name their pages with them.
The 0.0.0.0 doesn't work for me.
These have been residing in my host file for some time now to keep clean KazaA Lite:
127.0.0.1
www.brilliantdigital.com #.url
127.0.0.1 desktop.kazaa.com #.url
127.0.0.1 shop.kazaa.com #.url
127.0.0.1
www.bonzi.com #.url
127.0.0.1
www.altnetp2p.com #.url
127.0.0.1 alpha.kazaa.com #.url
127.0.0.1
www.b3d.coml #.url
Not ONE problem there (yet, fingers crossed).
There are several lists of offending sites with hundreds of urls also residing side by side.
I use the restricted sites option for transitory "killing" or rapid changing offending urls, like the buggy ad that used to freeze the old Morpheus.
For heavy use of the restricted sites there is a shell extension that if installed automates the process with a right click and the option directly in the IE context menu.