claiming for monies owed by a company

angryperson

I am owed in excess of £8,000 by a company that sub-contracted me in to work for them on some projects. I have been invoicing them since March 2009 (with a note to state payment is to be made within 30 days) and they have agreed to pay my invoices each time I have chased them. However, I have still not recieved payment.
Today I served a statutory demand for payment, and I have since had a phone call from them telling me they were going to pay, but as a result of my formal demand, they will now 'see me in court'. I am aware that the next step would be to wait 21 days and then apply for a 'winding up' order from the court, but the cost of this is quite high, and I am not sure if I would be able to recover this money.
I have no doubt that I am owed this money, and the company has not supplied any reason for failing to pay. What makes it worse is that the owner of the company was a good friend of mines for over 30 years. I have no interest in mending the friendship as it has gone totally beyond repair, but it is still sad that it has come to this.

Any ideas on what else I can do to scare these people into paying before having to either pay out myself for legal costs, or give up on this money? I would be thankful for any useful advice.