Fire-Steam feature is that it allows you to download
games such as: Counter-Strike: Source and Half-Life without the need for a ready-GCF files.
Also it allows you to play not only in no-steam servers, but also on the official with disabled VAC
Playing on the license server is available in the following games:
Ricochet, Condition Zero, Counter-Strike, Counter-Strike: Source, Day of Defeat, Day of Defeat: Source, Deathmatch Classic, Half-Life 2: Deathmatch