Seems to be now on the website as follows:
What the fee covers
IPS does not make a profit. Passport fees cover the costs of providing passport services in the UK. Part of the fee is called 'the consular premium'. This covers the costs of providing consular help to British nationals who find themselves in difficulty while overseas.
Consulates and embassies
If you're interested in how the cost of a UK passport compares with that of passports around the world, check the comparison table from IPS.
International passport fee comparison table from IPS
The IPS link takes you to this PDF, which is continently.. bearing in mind IPS are saying it is a comparison table, laid out in every country's own currency... so for your info £77.50 as of 26th May 2011 is 89.15 EUR and 126.39 USD.
So we have one of the most expensive passports in the EU but still cheaper than a US one it seems.
My next question, who has ever used a British Consulate, other than for banqueting?