UK ATC
Whilst it is technically against the law to listen to UK ATC (hence liveatc.net do not have any UK streams), there is an E-Petition currently working it's way through the checking process, and due to go live in about a week that addresses the issue, and is asking the UK government to finally drop the law.
Will post a link once I have it (as said, be about a week), if anybody is interested.
SD