The Speed Demos Archive hosts Half-Life competition. The current proven World Record for a complete-game HL speedrun is 31 minutes, achieved by Blake "Spider-Waffle" Piepho on July 1st, 2006 (using 180 segments, which means new demo each 10th second). The best run through HL's Hazard Course is 3 minutes and 10 seconds, also by Blake Piepho.
Many runners choose to compete by making use of the Half-Life Bunny Mod. The fastest single-segment Bunny Mod run is 1 hours and 0 minutes, set by Spider-Waffle. Swaff also used to have the best Hazard course time using this mod, with 3 minutes and 5 seconds. However, it was beaten at October 24th 2008 by the SDA newcomer 'rayvex', achieving a time of 2:54 minutes.