In
http://typophile.com/node/95635 FF Bradlo is mentioned as
the first font to apply traps aesthetically and the year given is 1995. Since my youth I always admired Metron (1971–1972) by Jiří Rathouský*, a custom job for the Prague Metro. That's why I used traps in Mentone (2008). Below is Metron in use at the "Museum" station, Prague, pic. Wikipedia:

*The authorship of Metron was contested by Prof. Petr Tučný, whose drawings, dated 1967–8 are below:


Source article (in Czech)
here.
František Štorm digitised Metron, afaik, but does not offer it for sale currently?
Comments
Thank you for sharing. Gives me a few new ideas