I'll let you do your own research on this, but I have it on good authority today that Nominet are clamping down on these. There were several very strong keyword .ltd.uk domains registered in 2007 off the back of the flawed Nominet algorithm that checks for .ltd.uk domain registration compliance. The "real" limited company hasn't bothered to register the .ltd.uk domain so a few entrepreneurs (three specifically) have taken 'opportunities'. Rules: Rules 10.3.4 -- this is going to be expanded to include "@" despite the fact that Companies House don't care. Get Companies House up in your browser, and a whois client in another window and take a look yourself. Please don't ask me to post examples.