Dauntless is currently parked in the dock at the foot of the University of East London's Docklands campus. She's been there since Friday, either protecting London from inappropriate celebrations of 9/11, or perhaps protecting UEL's First Week celebrations from anyone throwing cricket balls at Mach 3.
By my calculations, UEL gets about £55 million a year of UK Government funding (overwhelmingly HEFCE grant), whilst Dauntless cost a little over £1 billion (including her share of class development costs). In other words just building the ship, before any running costs, has set the British taxpayer back about 19.5 UEL-years.
Over those 19.5 years, UEL can be expected to graduate 63,653 FT students from first degree programmes (using the data in HESA Table T5 as a guide), in addition to PT and postgraduate students. There may even be some useful research into health, or maybe the Olympics if that's more to your taste. By contrast, the Type 42 destroyers that Dauntless is replacing shot down 7 Argentine aircraft and 1 Iraqi missile in total across a class of 14 over a period of 36 years. This gives us a rough statement 1 enemy aircraft=127,306 friendly graduates, although if we factor in 19.5 years of Dauntless' running costs, its more like 1 aircraft=150,000 graduates.
Photo courtesy of Wikipedia, entirely without permission...