This is an interesting site that compares the relative "worth" of money between different time periods, using different scales.
For example,£1,000 from 1977 was worth the following in 2007
£4,477.19 using the retail price index
£7,553.93 using the average earnings
£8,740.36 using the per capita GDP
I don't pretend to understand the methodology behind it all, but it might be a Useful Thing for some people?