The one I see most people wearing is either the Optivisor, or an equivalent type. They seem to be the name in head mounted magnifers.
A quick search on ebay came up with a page of possibles.
http://cgi.ebay.co.uk/OPTIVISOR-OPTICAL-GLASS-BINOCULAR-MAGNIFIER-DA-5_W0QQitemZ150183002113QQihZ005QQcategoryZ121893QQssPageNameZWDVWQQrdZ1QQcmdZViewItemhttp://cgi.ebay.co.uk/OPTIVISOR-WITH-4-AUXILIARY-LENSES_W0QQitemZ290183841729QQihZ019QQcategoryZ150083QQssPageNameZWDVWQQrdZ1QQcmdZViewItemI haven't seen anything as "minimal as in the article I must admit.
I favour the Optivisor from the point of view it uses optical ground glass lenses. My eyes are bad enough without doing more damage.
Got to admit the only thing holding me back is the possible weight issue and the fact my wife is going to take the mickey out of me even more wearing them than she does over my modelling now !!
I currently use a magnifier on an flexible arm which I find slightly restrictive, never in the right place, and the arm gets in the way sometimes, but I cant do without it the old peepers have got that bad !!
I'd love to get something to replace it and those look very unobtrusive, light wieght but I guess it'll be Optivisor in the end, as the UK does not seem to have the ones mentioned in the article.
Alan