Half-Life & Portal Universe with Wiki links.

Black Mesa Source
http://www.blackmesasource.com/

The TC for HL1 converts the original game to the HL2-source generation game engine for improved graphics and sound. Please note that the Source Engine from Half-Life 2 is now quite old. Regardless the HL2-source engine is head-and-shoulders above the HL1-engine. This TC makes for a nice trip down memory lane of the classic Half-Life that began the series.