The URLBlackList works great for the most part, and is quite flexible. However, what would be a fantastic additional policy is a simple URL keyword block that doesn't deconstruct the URL at all, but simply looks for the blocked strings and blocks the address if it finds any of them.

One example for this is "site%3Adrive.google.com" - this would block any Google searches within drive.google.com. Currently this can't be achieved, because:

*?q=site%3Adrive.google.com* doesn't work for me at all (presumably because the URLWhitelist entry for google.com is taking precedence).

https://www.google.co.uk/search?q=site%3Adrive.google.com* this works, but what if I'm searching for a particular term, and put that term first?:

https://www.google.co.uk/search?q=search+term+site%3Adrive.google.com now the above URLBlackList filter doesn't match.

Bottom line: URLBlackList is very powerful and flexible, but a simple string match filter would complement it greatly.