According to the British government's nifty new gadget for comparing salaries, the answer seems to be: none.
The most lucrative alternative to banking, according to UK statistics is piloting an aircraft, or being a chief executive. And then you'll come nowhere near to earning the £150k that the average front office banker earns in total compensation by the age of 28.
Things might not be that bad, however. We understand that lawyers and consultants are also well paid, but they seem strangely absent from the government's chart.