Rollers were my immediate thought as to how to get the juice out. Would love one of their engineers to chime in and talk about the reasons they built it that way.
I earned between 35-50k when I was there ('08-'11). Salaries are crazy low. The secret is actually contract work. Friends of mine were doing bog standard java dev work, and taking home between 80-100 £/hr. It was big company work so it was full time, 40 hours a week type of work.
As others have said, finance is the way in London. Better salaries, better perks.