I have recently begun a similar project: I work for a private bank and am rebuilding our client website. The main system (which is used internally for booking t

I have recently begun a similar project: I work for a private bank and am rebuilding our client website. The main system (which is used internally for booking transactions and managing portfolios etc.) runs on an Oracle DBMS, so it isn't really legacy, but it does have a goulash data schema that is convoluted and slow. I'm using Rails for the site, which of course assumes certain conventions, but I've actually found it easy to loosely couple the site to the old system (by using views to extract the relevant data plus a little extra Ruby code). Most people in my dept haven't even heard of RoR but I've already had a positive reaction to the proof of concept which blows the old site out of the water and was built in less than a week. The UI advice in the article hits the nail on the head. When dealing with legacy systems, smart use of aggressive caching and AJAX (loading icons etc.) can help improve user experience without any changes to the underlying system.