Business Diary: Few reasons to party at Luminar

These are worrying times for shareholders in Luminar, the nightclubs operator, which is working on a recovery plan it hopes will appease the banks that agreed to waive its debt covenants earlier this year. A surprise change of auditor this week added to nervousness about the firm and now it has had to warn investors that they may be targeted by fraudsters. "It has come to our attention that some of our shareholders have received unsolicited phone calls from 'companies' offering to buy their shares for substantially more than current market value," Luminar warns. Don't take the bait, it warns – it's a classic boiler-room scam.

BHP lays down law to staff

Staff in the Brisbane office of London-listed mining giant BHP Billiton have been told to tidy themselves up. A memo from HR is doing the rounds, warning them to keep their office tidy and to be more considerate – there's a ban on loud mobile phone ringtones, for example, as well as on eating at your desk. No smelly food is to be brought into the office – and staff who throw their jackets over the back of the chairs need to hang them up properly. The Sydney Morning Herald claims the edicts come right from the top – BHP CEO Marius Kloppers.

Banks lose 4,000 staff in 90 minutes

Banks have a reputation for being ruthless, but this is impressive. Each year, the British Bankers' Association sends out a digest of fascinating facts about the banking industry. This year's publication included the claim that BBA members employ 401,800 staff. An hour and a half later, a correction arrives: the correct number is 397,800. So that's 4,000 workers shuffled out of the door in 90 minutes – good going, even by the banking sector's standards.

Ryanair gets ready to strip

Our good deed for the day is to advertise the fact that Ryanair has begun looking for a charity to benefit from sales of its 2012 calendar. It's not an initiative for everyone, since some people get cross about the calendar's models – basically, its best-looking female cabin staff in various states of undress and provocative poses – but it does raise a great deal of money. Ryanair says it is aiming for €100,000 this time around.