Finally, the Half-Life saga can be played on-line, multiplayer, all vehicles, and with additional modes that extend the gameplay beyond mere single-player and Deathmatch combined! This demo release contains the full Canals levels (Chapters 3 and 4), and illustrates both the playability of the Co-Operative Mode, and the sheer ruthless fun of Racing Mode, with up to six friends
http://www.fileplanet.com/171987/170000/fileinfo/Half-Life-2---Follow-Freeman-Co-Op-Client
Also available here:
http://halflife2.filefront.com/file/HalfLife_2_Coop_Follow_Freeman_Client_Files;73694