Magdeburg solution is my name after seeing such beams in front of low bridges in Magdeburg in 1996. they also have another even more drastic solution 600V tram wires. That I'd like to see more of this country because it would mean more trams, the finest form of inner urban transport, and before any says that they impede the traffic that's why they are so good!
Alas, City of Edinburgh Council is destroying the case for trams single-handed. For the latest, see
http://www.bbc.co.uk/news/uk-scotland-edinburgh-east-fife-14678578 - the trams will only operate from the Airport to Haymarket station. Digging up Princes Street was (a) pointless and (b) apparently needs to be done again (!).
http://www.youtube.com/watch?v=7yOqU4-zE5w has the usual Hitler rant - "^500 million quid to replace the number 22 bus".