We came in #3, beat out by Sven-Coop and NS. They used the brokenish 1.3 build and got the release date horribly wrong, but still cool.
http://www.moddb.com/features/10-years-of-half-life
http://www.moddb.com/features/10-years-of-half-life
It is still a mod, but that video is only for non-comercial mods of half-life. Did they based the classification of esf as esf 1.3 beta or esf 1.2.3? In the video it shows 1.3 beta, but is hard to believe that in incomplete game is such in a position like the third.ESF should have been #2, and Counter-Strike ( it was a mod up until the times of 1.6 ) as #3 IMHO.